Windows 2000 Tips &
Tweaks -
BIOS Settings
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< Windows 2000 Tips & Tweaking Guide created by Michael
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SOFTMENU 2/3 OVERCLOCKING SETTINGS
Video BIOS shadowing / cacheable.
Shadow address ranges xxxxx - xxxxx.
SDRAM CAS latency time/SDRAM cycle length.
PCI pipeline / PCI pipelining.
Bank 0/1, 2/3, 4/5 DRAM timing.
PCI Concurrency (Concurrent PCI/Host).
Ultra DMA-66/100 IDE controller.
Force Update ESCD / Reset Configuration Data.
PIRQ_0 use IRQ No. PIRQ 3 Use IRQ No..
SOFTMENU 2/3 OVERCLOCKING SETTINGS..
Introduction
By modifying settings in your BIOS you can improve performance, reduce boot time, fix incompatibility problems & many other things. This guide will take you through the BIOS & how to update it, change setting to improve performance. Some of these settings are from various sources e.g. motherboard manuals and from my own experience but the majority of these settings are taken from 'Tweaking and Optimizing Windows' file from Xen - thank you Paul.
del during boot ---> AMI, Award
Esc during boot ---> Toshiba
F1 during boot ---> Toshiba; Phoenix; Late model PS/1 Value Point and 330s
F2 during boot ---> NEC
F10 when square in top RH corner of screen ---> Compaq
Ins during boot ---> IBM PS/2s w/ Reference Partition
Reset twice Some ---> Dells
Alt Enter ---> Dell
Alt ? some ---> PS/2s
Ctrl-Esc ---> General
Ctrl Ins some ---> PS/2s when pointer at top right of screen
Ctrl Alt Esc ---> AST Advantage, Award, Tandon
Ctrl Alt + ---> General
Ctrl Alt S ---> Phoenix
Ctrl Alt Ins ---> Zenith, Phoenix
Ctrl S ---> Phoenix
Ctrl Shift Esc ---> Tandon 386
Shift Ctrl Alt + Num Pad del ---> Olivetti PC Pro
Setup disk Old ---> Compaqs, Epson (Gemini), IBM, IBM PS/2, Toshiba, most old 286s
You can boot up faster & improve your performance by changing settings in your BIOS. First of all need to access it. When you're starting the PC, hit the Delete key. It should bring up the BIOS a few seconds later. Use another key if necessary.
You may need to search under different sections of your BIOS to find these, so be prepared to look. I'll put these into different sub-categories where they generally would appear.
SOFTMENU 2/3 OVERCLOCKING SETTINGS
FINAL NOTE
Shadowing/caching. While shadowing/caching can improve performance in some cases, if the area of memory used for the shadowing/caching purposes is written to your system (or program at least) will crash. BIOS shadowing/caching is particularly worthless as your BIOS is only needed at startup, or possibly when in DOS mode (particularly the video card BIOS). Basically your RAM/cache is better used for other purposes where it will improve performance, rather than where it might improve performance.
Use this to set the date for the computer to use.
Use this to set the time for the computer to use.
There are more options available for selection in a submenu. Many of the parameters for the options below will be shown on your hard drive, so write them down if possible (Note these fields are only necessary for hard drives, not for DVD drives, etc.). Many of the settings used here will be printed on your hard drive.
This can be used to auto-detect all parameters for the values shown below. Press Enter to try auto-detection.
Use this to set the access mode for the hard drive. Set this to Auto if you are unsure. Set to Normal if the hard drive is less then or equal to 528MB (highly unlikely now). Set to LBA (Logical Block Addressing) for large disk support. If LBA mode is not supported try Large mode instead.
Enter in the size (in MB) of the hard drive.
Use this field to set the number of cyclinders on the hard drive.
Use this to set the number of read/write heads on the hard drive.
See IDE Primary master.
See IDE Primary master.
See IDE Primary master.
Select the type of floppy drive you have installed in your machine, if any.
Select the type of the second floppy drive you have installed in your machine, if any.
If you are using a Japanese PC then you'll most likely be using this type of floppy drive, in which case you should set it to Drive A/B depending on which drive it is installed as. All others should set this to Disabled.
Sets the VGA mode for your graphics card. Leave this set to EGA/VGA.
When Enabled if any attempt to access the Boot sector or Partition table is made the BIOS will warn you & either ask you too allow it to make changes or disable any changes. While safer to leave enabled it can interfere with certain updates & programs, particularly Partition Magic. I'd recommend leaving it set to disabled.
Make sure to enable this if not already enabled. The L1 cache is effectively extremely fast RAM, running at the same speed as the processor. This feature is useful for overclockers who want to pinpoint the cause of their unsuccessful overclocking. I.e. if a CPU cannot reach 500MHz with the L1 cache enabled and vice versa; then the L1 cache is what's stopping the CPU from reaching 500MHz stably. However, disabling the L1 cache in order to increase the overclockability of the CPU is a very bad idea, especially in highly pipelined designs like Intel's P6 family of processors (Pentium Pro, Celeron, Pentium II, Pentium !!!).
Make sure to enable this if not already enabled. Some PC's (e.g. K6-3) may contain a L3 cache. Although most won't, but enable it if it does. The L2 cache is effectively extremely fast RAM, although the L2 cache generally runs at a fraction of CPU speed. On Pentium 3 E, or EB models the L2 cache runs at the same speed as the processor. This feature is useful for overclockers who want to pinpoint the cause of their unsuccessful overclocking. I.e. if a CPU cannot reach 500MHz with the L2 cache enabled and vice versa; then the L2 cache is what's stopping the CPU from reaching 500MHz stably. Users may choose to disable L2 cache in order to overclock higher but the trade-off isn't really worth it.
Set this to enabled. It will check your L2 cache for errors & can fix some of them. This will improve to the stability of your PC. This feature enables or disables the L2 cache's ECC checking function (if available). Enabling this feature is recommended because it will detect and correct single-bit errors in data stored in the L2 cache. It will also detect double-bit errors but not correct them. Still, ECC checking stabilizes the system, especially at overclocked speeds when errors are most likely to creep in. There are those who advocate disabling ECC checking because it reduces performance. The performance difference is negligible, if at all. However, the stability and reliability achieved via ECC checking is real and substantial. It may even enable you to overclock higher than is possible with ECC checking disabled. So, enable it for added stability and reliability.
This feature is only valid if you install a Pentium !!! processor. It will most probably not appear unless you have the Pentium !!! processor installed. This feature enables you to control whether the Pentium !!!'s serial number can be read by external programs. Enable this if your secure transactions require you to use such a feature. But for most people, I think you should disable this feature to safeguard your privacy.
When booting up a series of tests are run on a system. Enabling this feature will simplify these tests resulting in a faster boot-up. You should Disable this if your system is experiencing problems. When enabled, this feature will shorten some tests and skip others that are performed during the booting up process. Thus, the system boots up much quicker. Enable it for faster booting but disable it after making any change to the system to detect any errors that may slip through the Quick Power On Self Test. After a few error-free test runs, you can reenable this option for faster booting without impairing system stability.
For fastest boot up select your hard-drive only, usually C:. If you encounter problems you can change this later on.
Selects the first bootable device, choose where your operating system is stored, usually HDD-0 (Choose SCSI if appropriate). If you need to boot from a Floppy disk or CD-ROM, select appropriately. If this fails it will check the second boot device for a bootable media. NOTE - For optimal boot time set this to wherever your OS is stored.
Selects the second bootable device, where your operating system is stored, usualy HDD-0. If this fails it will check the third boot device for a bootable media. NOTE - For optimal boot time set this to Disabled.
Selects the third bootable device. If this fails it will check the other boot device for a bootable media. NOTE - For optimal boot time set this to Disabled.
Selects the other bootable device. NOTE - For optimal boot time set this to Disabled.
This function is only valid if the Boot Sequence function above has EXT settings and this function has to cooperate with the Boot Sequence function. This function allows you to set whether the system boots from an IDE hard disk that's connected to any of the extra two IDE ports found on some motherboards (i.e. ABIT BE6 and BP6) or a SCSI hard disk. To boot from an IDE hard disk that's connected to the 3rd or 4th IDE port, courtesy of the extra onboard IDE controller), you'll first have to set the Boot Sequence (above) function to start with EXT first. For example, the EXT, C, A setting. Then, you will have to set this function, Boot Sequence EXT Means to IDE. In order to boot from a SCSI hard disk, set the Boot Sequence (above) function to start with EXT first. For example, the EXT, C, A setting. Then, you will have to set this function, Boot Sequence EXT Means to SCSI.
This allows for quick swapping off floppy drive names, i.e. your A: drive changes to B: & B: changes to A:. By default this is Disabled & should be left at this unless you have, 1. - Multiple floppy drives (unlikely) & Need to swap around their drive names without having to swap cables around.
Use this setting to determine whether or not the BIOS will try to detect a FDD (Floppy Disk Drive) in your system. If enabled & no FDD is present then an error message will be displayed. I'd recommend setting this to disabled to skip this test & improve boot time.
disable this, if something happens you can re-enable it, but for now it slows boot-time. Only needed when you want to load from a bootable floppy, e.g. When wanting to flash your BIOS.
On or Off, this sets whether or not the NumLock key is enabled (on) when booting up. Its a matter of preference, although I find having the keyboard light on annoying. Either way its only a minor cosmetic setting for booting. This feature controls the functionality of the Numeric Keyboard at boot up. If set to On, the Numeric Keyboard will function in the numeric mode (for typing out numbers) but if set to Off, it will function in the cursor control mode (for controlling the cursor). The setting of this feature is entirely up to your preference.
This feature determines how Gate A20 is used to address memory above 1MB. When this option is set to Fast, the motherboard chipset controls the operation of Gate A20. But when set to Normal, a pin in the keyboard controller controls Gate A20. Setting Gate A20 to Fast improves memory access speed and thus, overall system speed, especially with OS/2 and Windows. This is because OS/2 and Windows enter and leave protected mode via the BIOS a lot so Gate A20 needs to switch often from enabled to disabled and back again. Setting this feature to Fast improves memory access performance above 1MB because the chipset is much faster in switching Gate A20 than the keyboard controller. It is recommended that you set it to Fast for faster memory accesses.
This setting allows for multi-sector transfers, enabled is faster. The IDE HDD Block Mode feature speeds up hard disk access by transferring data from multiple sectors at once instead of using the old single sector transfer mode. When you enable it, the BIOS will automatically detect if your hard disk supports block transfers and configure the proper block transfer settings for it. Up to 64KB of data can be transferred per interrupt with IDE HDD Block Mode enabled. Since virtually all hard disks now support block transfers, there is normally no reason why IDE HDD Block Mode should not be enabled. Although it has been known to cause data corruption in Windows NT.
If you IDE interface supports IDE prefetching this will allow for faster drive access. Enabled is faster, only disable if not supported.
Select enabled to use 32-bit I/O accesses with your hard drive. This is faster, although it has been known to cause data corruption in Windows NT.
This allows to edit the 2 settings below. Enable or Disable as you see appropriate.
This is the frequency at which the keyboard will repeat a keystroke, e.g. If set to 6 then the key will repeat the same character 6 times per second. This setting is the same as the Repeat rate in Keyboard properties applet in the Control panel.
This sets the delay in milli-seconds that you can hold a key down before it gets repeated, e.g. If set to 500msec, then you can hold down a key for 1/2 a second before it starts repeating. This setting is the same as Repeat delay in Keyboard properties applet in the Control panel.
Settings available for this are System or Setup. Depending on which option is selected a user will prompted to enter in a password when either - booting the system (System) or when trying to enter the BIOS (Setup). See later on in the guide for where to set the password.
If you have an MPEG card or add-on card then you should try set this to enabled to remove the colour inversion that can occur. Disable it if you have no MPEG card in your machine, or do not get affected by any colour inversion.
Set this to enabled. Nearly all video cards now need an IRQ assigned to them to function correctly. Many high-end graphics accelerator cards now require an IRQ to function properly. Disabling this feature with such cards will cause improper operation and/or poor performance. Thus, it's best to make sure you enable this feature if you are having problems with your graphics accelerator card. However, some low-end cards don't need an IRQ to run normally. Check your graphics card's documentation (manual). If it states that the card does not require an IRQ, then you can disable this feature to release an IRQ for other uses. When in doubt, it's best to leave it enabled unless you really need the IRQ.
This option is only valid for multiprocessor motherboards as it specifies the version of the Multiprocessor Specification (MPS) that the motherboard will use. The MPS is a specification by which PC manufacturers design and build Intel architecture systems with two or more processors. MPS version 1.4 added extended configuration tables to improve support for multiple PCI bus configurations and improve future expandability. It is also required for a secondary PCI bus to work without the need for a bridge. Newer versions of server operating systems will generally support MPS 1.4 and as such, you should change the BIOS Setup from the default of 1.1 to 1.4 if your operating system supports version 1.4. Leave it as 1.1 only if you are running older server OSes. WinNT should be 1.4.
If you have 64MB RAM or more in your system & are running OS/2 then set this to OS/2. If you have another operating system installed select Non-OS/2.
This option enables/disables support for the hard disk's S.M.A.R.T. capability. The S.M.A.R.T. (Self Monitoring Analysis And Reporting) technology is supported by all current hard disks and it allows the early prediction and warning of impending hard disk disasters. You should enable it so that S.M.A.R.T. aware utilities can monitor the hard disk's condition. Enabling it also allows the monitoring of the hard disk's condition over a network. There's no performance advantage in disabling it even if you don't intend to use the S.M.A.R.T. technology.
If using Windows 95 (still) & have no Floppy drive in your machine set this to Yes, otherwise leave it at No.
Some hard drives may require some spin-up time to be identified correctly. This settings sets how long the delay is in seconds. 0 is the shortest (no delay). This is similar to the BootDelay=x setting that could be used in Windows 95's msdos.sys. Try setting it to 0 before using higher values.
Video BIOS shadowing / cacheable
Your system will perform better with this setting at disabled. As you can read in the MS Knowledge base, shadowing is not an advantage. Only enable this if you still use DOS mode a lot, where it can improve performance.
Your system does not access the video cards BIOS, it uses drivers to do so. Only enable this if you still use DOS mode games a lot, where it can improve performance. What Video RAM Caching does is cache the data of the Video RAM. This data is used by the graphics processor, not the CPU. So, it would be rather pointless for the CPU's L2 cache to cache the Video RAM because the data will have to go through the slow AGP bus twice to reach the graphics processor. The Video RAM-to-graphics processor's bandwidth is incredibly high compared to the bandwidth of the AGP bus and also the system RAM. So, the L2 cache would be better utilized to speed up the system RAM.In today's accelerated video cards, the main job of the video BIOS is to provide a program for the video processor (RIVA TNT2, Voodoo3, etc) to run so that it can do its job. Interface between the video card and software is done through a command set provided by the driver and really has nothing to do with the video BIOS. The original BIOS function are still available to maintain backwards VGA compatibility. BIOS shadowing can cause SERIOUS and permanent harm to the video card itself... After a failed 'shadowed' flash, the card was never again able to render DOS video modes or text; and further BIOS updates would not work since they 'failed to detect current BIOS revision'.
Shadow address ranges xxxxx - xxxxx
Where, xxxxx - xxxxx represents the address ranges to be shadowed in RAM. I'd recommend setting these to Disabled. This can improve system stability.
BIOS CHIPSET FEATURES
SDRAM CAS latency time/SDRAM cycle length
This sets the CAS latency timing of the DRAM system memory access cycle when SDRAM system memory is installed. Setting this to 2 will yield better performance, although may be less stable if your SDRAM is not CAS2 rated. 3 is slower & should be used when SDRAM isn't CAS2 rated or you want to improve stability. NOTE - CAS2 can significantly improve performance in many ways.
This feature toggles the minimum number of clock cycles required for the Tras and the Trc of the SDRAM. Tras refers to the SDRAM's Row Active Time, which is the length of time in which the row is open for data transfers. It is also known as Minimum RAS Pulse Width. Trc, on the other hand, refers to the SDRAM's Row Cycle Time, which determines the length of time for the entire row-open, row-refresh cycle to complete. The default setting is 6/8 which is more stable and slower than 5/6. However, 5/6 cycles the SDRAM faster but may not leave the row open long enough for data transactions to complete. This is especially true at SDRAM clockspeeds above 100MHz. Therefore, you can try 5/6 for better SDRAM performance but should increase it to 6/8 if your system becomes unstable.
this should be set to a low number, although it is affected by the quality of you RAM, so set it higher if you have any difficulties afterwards. This option allows you to insert a delay between the RAS (Row Address Strobe) and CAS (Column Address Strobe) signals. This occurs when the SDRAM is written to, read from or refreshed. Naturally, reducing the delay improves the performance of the SDRAM while increasing it reduces performance. So, reduce the delay from the default value of 3 to 2 for better SDRAM performance. However, if you are facing system stability issues after reducing the delay, reset the value back to 3.
This option sets the number of cycles required for the RAS to accumulate its charge before the SDRAM refreshes. Reducing the precharge time to 2 improves SDRAM performance but if the precharge time of 2 is insufficient for the installed SDRAM, the SDRAM may not be refreshed properly and it may fail to retain data. So, for better SDRAM performance, set the SDRAM RAS Precharge Time to 2 but increase it to 3 if you face system stability issues after reducing the precharge time.
This feature is similar to SDRAM CAS Latency Time. It controls the time delay (in clock cycles - CLKs) that passes before the SDRAM starts to carry out a read command after receiving it. This also determines the number of CLKs for the completion of the first part of a burst transfer. Thus, the lower the cycle length, the faster the transaction. However, some SDRAM cannot handle the lower cycle length and may become unstable. So, set the SDRAM Cycle Length to 2 for optimal performance if possible but increase it to 3 if your system becomes unstable.
This option allows you to adjust the leadoff time needed before the data stored in the SDRAM can be accessed. In most cases, it is the access time for the first data element in a burst. For optimal performance, set the value to 3 for faster SDRAM access times but increase it to 4 if you are facing system stability issues.
For best performance set this to 4-bank/way, although lower settings may help improve stability. This feature enables you to set the interleave mode of the SDRAM interface. Interleaving allows banks of SDRAM to alternate their refresh and access cycles. One bank will undergo its refresh cycle while another is being accessed. This improves performance of the SDRAM by masking its refresh time of each bank. Each SDRAM DIMM consists of either 2 banks or 4 banks. 2-bank SDRAM DIMMs use 16Mbit SDRAM chips and are usually 32MB or less in size. 4-bank SDRAM DIMMs, on the other hand, usually use 64Mbit SDRAM chips though the SDRAM density may be up to 256Mbit per chip. All SDRAM DIMMs of at least 64MB in size or greater are 4-banked in nature. If you are using a single 2-bank SDRAM DIMM, set this feature to 2-Bank. But if you have two 2-bank SDRAM DIMMs, you can use 4-Bank as well. If you are using 4-bank SDRAM DIMMs, you can set either 2-Bank or 4-Bank interleave. Naturally, 4-bank interleave is better than 2-bank interleave so if possible, set it to 4-Bank. Use 2-Bank only if you are using a single 2-bank SDRAM DIMM. Note, however, that Award (now part of Phoenix Technologies) recommends that SDRAM bank interleaving be disabled if 16Mbit SDRAM DIMMs are used.
This feature determines whether the processor or the SDRAM itself controls the precharging of the SDRAM. If this option is disabled, all CPU cycles to the SDRAM will result in an All Banks Precharge Command on the SDRAM interface which improves stability but reduces performance. If this feature is enabled, precharging is left to the SDRAM itself. This reduces the number of times the SDRAM is precharged since multiple CPU cycles to the SDRAM can occur before the SDRAM needs to be refreshed. So, enable it for optimal performance unless you are facing system stability issues with this option enabled.
In the unlikely event you have ECC (Error Correcting Code) memory installed then you should set this to ECC, otherwise set it to non-ECC. Most memory is non-ECC & not really recommended for most users unless the need the added stability (but it is slower when ECC is being used).
This is a DRAM optimization feature. If a memory read is addressed to a location whose latest write is being held in a buffer before being written to memory, the read is satisfied through the buffer contents, & the read is not sent to the DRAM. Set this to Enabled for better performance.
Set this to disabled. The system BIOS is very rarely accessed when you are using your PC after it boots up.
Set this to disabled. The video card RAM is more efficient than caching it & make your system more stable as well.
This feature enables or disables the caching of the video RAM at A0000h-AFFFFh via the L2 cache. This is supposed to speed up accesses to the video RAM. However, this does not translate into better system performance.
Many graphics cards now have a RAM bandwidth of 5.3GB/s (128bit x 166MHz DDR) and that number is climbing constantly. Meanwhile, SDRAM's bandwidth is still stuck around 0.8GB/s (64bit x 100MHz) or at most 1.06GB/s (64bit x 133MHz) if you are using a PC133 system. Now, although a Pentium !!! 650 may have a L2 cache bandwidth of about 20.8GB/s (256bit x 650MHz), it makes more sense to cache the really slow system SDRAM instead of the graphics card's RAM.
Also note that caching the video RAM doesn't make much sense even with the Pentium !!!'s high L2 cache bandwidth. This is because the video RAM communicates with the L2 cache via the AGP bus which has a maximum bandwidth of only 1.06GB/s using the AGP4X protocol. Actually, that bandwidth is halved in the case of the L2 cache caching the graphics card's RAM because data has to pass in two directions. In addition, if any program writes into this memory area, it will result in a system crash. So, there's very little benefit in caching the video card's RAM. It would be much better to use the processor's L2 cache to cache the system SDRAM instead. It is recommended that you disable Video RAM Cacheable for optimal system performance.
Some old add-in cards need this enabled to work properly. If you have such a card then enable this, otherwise disable it. If you enable this function, your OS can only use up to 15MB of RAM, irrespective of how much RAM your system actually has. So, always disable this function unless your ISA card absolutely requires this memory area to work properly.
The lower the setting the better, with N/A being the best. Set it to N/A if you have no ISA bus cards in your system, if you do try setting it to 1 instead. Increase the value to fix problems with ISA based cards.
The lower the setting the better, with N/A being the best. Set it to N/A if you have no ISA bus cards in your system, if you do try setting it to 1 instead. Increase the value to fix problems with ISA based cards.
Passive release is intended to lower CPU utilisation by allowing bus mastering devices to access RAM interleaved with CPU accesses. Most useful when playing multimedia files (such as MPEG's or other streaming multimedia). You should enable this if you fall into that category, otherwise disable it.
This is required for compliance with the PC 2.1 specification. It allows for support of delay transaction cycles. Set it to enabled.
This is the same thing as Delayed Transaction above. This feature is used to meet the latency of PCI cycles to and from the ISA bus. The ISA bus is much, much slower than the PCI bus. Thus, PCI cycles to and from the ISA bus take a longer time to complete and this slows the PCI bus down. However, enabling Delayed Transaction enables the chipset's embedded 32-bit posted write buffer to support delayed transaction cycles. This means that transactions to and from the ISA bus are buffered and the PCI bus can be freed to perform other transactions while the ISA transaction is underway. This option should be enabled for better performance and to meet PCI 2.1 specifications. Disable it only if your PCI cards cannot work properly or if you are using an ISA card that is not PCI 2.1 compliant.
This option selects the size of the AGP aperture. The aperture is a portion of the PCI memory address range dedicated as graphics memory address space. Host cycles that hit the aperture range are forwarded to the AGP without need for translation. This size also determines the maximum amount of system RAM that can be allocated to the graphics card for texture storage. AGP Aperture size is set by the formula : maximum usable AGP memory size x 2 plus 12MB. That means that usable AGP memory size is less than half of the AGP aperture size. That's because the system needs AGP memory (uncached) plus an equal amount of write combined memory area and an additional 12MB for virtual addressing. This is address space, not physical memory used. The physical memory is allocated and released as needed only when Direct3D makes a "create non-local surface" call.
The size of the aperture does not correspond to performance so increasing it to gargantuan proportions will not improve performance. Many graphics card, however, will require a larger than 8MB AGP aperture size to work properly so you will need to set a minimum of 16MB for the AGP aperture size. Even then, you should set the aperture size at a higher setting so that it will be large enough to accommodate any texture storage requirements that your games/applications may have. At the moment, the rule of the thumb is an AGP aperture size of about 64MB to 128MB. Increasing the AGP aperture size beyond 128MB wouldn't really hurt performance but it would still be best to keep the aperture size to about 64MB-128MB so that the GART table won't be too large. As the amount of onboard RAM increases and texture compression becomes commonplace, there's less of a need for the AGP aperture size to increase beyond 64MB. So, it's recommended that you set the AGP Aperture Size as 64MB or at most, 128MB.
By default, the AGP busmastering device waits for at least 2 wait states or AGP clock cycles before it starts a read transaction. This BIOS option allows you to reduce the delay to only 1 wait state or clock cycle. For better AGP read performance, enable this option but disable it if you experience weird graphical anomalies like wireframe effects and pixel artifacts after enabling this option.
By default, the AGP busmastering device waits for at least 2 wait states or AGP clock cycles before it starts a write transaction. This BIOS option allows you to reduce the delay to only 1 wait state or clock cycle. For better AGP write performance, enable this option but disable it if you experience weird graphical anomalies like wireframe effects and pixel artifacts after enabling this option.
USWC or Uncacheable Speculative Write Combination improves performance for Pentium Pro systems (and possibly other P6 processors as well) with graphic cards that have a linear framebuffer (all new ones do). By combining smaller data writes into 64-bit writes, it reduces the number of transactions required for a particular amount of data to be transferred into the linear framebuffer of the graphics card. However, it may cause issues like graphic corruption, crashes, booting problems, etc... if the graphics card does not support such a feature.
So, if you are using a Pentium Pro processor or a motherboard based on older chipsets, enable it for faster graphics performance. If you own a newer motherboard, you can try enabling it but make sure you run some tests to determine if this feature really improves performance or not. It's quite possible that it may not anything at all or even decrease performance.
Set this to disabled. This has to do with EMC (Electro-Magnetic Compatibility) testing. As a result you shouldn't need to enable it at all. Unless, you get intereference as a result. This is similar to radio signals affecting unshielded speakers. Setting this to enabled varies the bus speed a little so that system doesn't emit intereference at the same frequency. This affects performance however.
This function is similar to the Smart Clock option of the Spread Spectrum function. The BIOS monitors the AGP, PCI and SDRAM's activity. If there are no cards in those slots, the BIOS turns off the appropriate AGP, PCI or SDRAM clock signals. And when there's no activity in occupied AGP / PCI / SDRAM slots, the BIOS turns off those clock signals as well. This way, EMI (Electromagnetic Interference) can be reduced without compromising system stability. This also allows the computer to reduce power consumption because only components that are running will use power. Still, if you do not have any EMI problem, leave the setting at Disabled for optimal system stability and performance. Enable it only if you are plagued by EMI or if you want to save more power.
This function protects the BIOS from accidental corruption by unauthorized users or computer viruses. When enabled, the BIOS' data cannot be changed when attempting to update the BIOS with a Flash utility. To successfully update the BIOS, you'll need to disable this Flash BIOS Protection function. You should enable this function at all times. The only time when you need to disable it is when you want to update the BIOS. After updating the BIOS, you should immediately re-enable it to protect it against viruses.
This function is useful for file servers and routers, etc., which need to be running 24 hours a day. When enabled, the system's hardware reset button will not function. This prevents the possibility of any accidental resets. When set as Disabled, the reset button will function as normal. It is recommended that you leave it as Disabled unless you are running a server.
This is a BIOS function that introduces a small delay before the system reads data from a DRAM module. This feature was added to facilitate the use of some special SDRAM modules that have unusual timings. You need not enable this feature unless you experience strange system crashes that you suspect is due to memory instability. So, it's recommended that you leave it as Disabled unless you are experiencing some system stability issues. In that case, you can enable this BIOS function to see if your DRAM module is one of those with unusual timings and to correct that problem.
This BIOS function controls the timing for reading the next bank of data when DRAM Interleave or SDRAM Bank Interleave is enabled. Naturally, the lower the time you use, the faster the DRAM modules can interleave and consequently, the better the performance. So, it is recommended that you set the time as low as possible for better DRAM performance. Increase the DRAM interleave time only if you face system stability problems.
Byte merging holds 8-bit or 16-bit writes from the CPU to the PCI bus in a buffer where it is accumulated and merged into 32-bit writes. The chipset then writes the data in the buffer to the PCI bus when it can. As you can see, merging 8-bit or 16-bit writes reduces the number of PCI transactions, thus freeing up both bandwidth and CPU time. So, it's recommended that you enable this feature for better PCI performance.
This BIOS function combines PCI or CPU pipelining with byte merging. Byte merging is then used to enhance performance of the graphics card. This function controls the byte-merge feature for framebuffer cycles. When Enabled, the controller checks the eight CPU Byte Enable signals to determine if data bytes read from the PCI bus by the CPU can be merged. So, it's recommended that you enable this feature for better performance with your PCI graphics card. Other PCI devices may benefit from this feature as well.
This BIOS option controls the timing of the RAM. If you enable it, switching between reads and writes will be faster. Although the default is Disabled, you should enable it for better RAM performance unless you face stability problems after enabling it.
This controls the CPU write buffer to the PCI bus. If this buffer is disabled, the CPU writes directly to the PCI bus. Although this may seem like the faster and thus, the better method, this isn't true. Because the CPU bus is faster than the PCI bus, any CPU writes to the PCI bus has to wait until the PCI bus is ready to receive data. This prevents the CPU from doing anything else until it has completed sending the data to the PCI bus. Enabling the buffer enables the CPU to immediately write up to 4 words of data to the buffer so that it can continue on another task without waiting for those 4 words of data to reach the PCI bus. The data in the write buffer will be written to the PCI bus when the next PCI bus read cycle starts. The difference here is that it does so without stalling the CPU for the entire CPU to PCI transaction. Therefore, it's recommended that you enable the CPU to PCI write buffer.
This BIOS option controls the PCI write buffer. If this is enabled, then every write transaction on the PCI bus goes straight to the write buffer. Burst transactions are then sent on their way immediately. If this option is disabled, the data will go to the write buffer and burst-transferred later (when the PCI bus is free) if the write transaction is a burst transaction. If the write transaction is not a burst transaction, then the write buffer is flushed and the data is written to the PCI bus immediately. It is recommended that you enable PCI Dynamic Bursting for better PCI performance.
This function determines whether there's a delay before any writes to the PCI bus. If this is enabled, then writes to the PCI bus are executed immediately (with zero wait states), as soon as the PCI bus is ready to receive data. But if it is disabled, then every write transaction to the PCI bus is delayed by one wait state. Normally, it's recommended that you enable this for faster PCI performance. However, disabling it may be useful when overclocking the PCI bus results in instability. The delay will generally improve the overclockability of the PCI bus.
This feature is similar to the Delayed Transaction BIOS option. It is used to meet the latency of PCI cycles to and from the ISA bus. The ISA bus is much, much slower than the PCI bus. Thus, PCI cycles to and from the ISA bus take a longer time to complete and this slows the PCI bus down. However, enabling Delayed Transaction enables the chipset's embedded 32-bit posted write buffer to support delayed transaction cycles. This means that transactions to and from the ISA bus are buffered and the PCI bus can be freed to perform other transactions while the ISA transaction is underway. This option should be enabled for better performance and to meet PCI 2.1 specifications. Disable it only if your PCI cards cannot work properly or if you are using an ISA card that is not PCI 2.1 compliant.
If this BIOS feature is enabled, the AGP bus will attempt to access a busy PCI bus for a limited time before giving up. Another AGP request will be required to attempt another PCI bus access. But if this feature is disabled, the AGP bus will keep trying to access the PCI bus until it successfully does so. Manufacturers recommend that you leave it as enabled but AGP bus performance may improve with this feature disabled.
This feature controls the CPU's access to the PCI bus. If you choose 1 PCI, the CPU will always be granted access right after the current PCI bus master transaction completes, irrespective of how many other PCI bus masters are on the queue. This affords the quickest CPU access to the PCI bus but means poorer performance for the PCI bus devices.
If you choose 2 PCI, the CPU will be granted access after the current and the next PCI transaction completes. In other words, the CPU is guaranteed access after two PCI bus master transactions, irrespective of how many other PCI bus masters are also on the queue. This means the CPU has to wait a little longer than with the 1 PCI option but PCI devices will have quicker access to the PCI bus. If you choose 3 PCI, the CPU will only be granted access to the PCI bus after the current PCI bus master transaction and the following two PCI bus master transactions on the queue have been completed. So, the CPU has to wait for three PCI bus masters to complete their transactions on the PCI bus before it can gain access to the PCI bus itself. This means poorer CPU-to-PCI performance but PCI bus master devices will enjoy better performance.
But irrespective of your choice, the CPU is guaranteed access to the PCI bus after a maximum of 3 PCI master grants. It doesn't matter if there are numerous PCI bus masters on the queue or when the CPU requested access to the PCI bus. It will always be granted access after one PCI bus master transaction (1 PCI), two transactions (2 PCI) or three transactions (3 PCI).
This feature is only found on motherboards that support AGP4X. However, it's usually set to Disabled by default because not everyone will be using an AGP4X card with the motherboard. For users of AGP1X or 2X cards, this BIOS option needs to be disabled for the cards to work properly. In order to prevent complications, manufacturers prefer to just disable AGP4X mode. However, this means users of AGP4X cards will lose out on the greater bandwidth afforded by the AGP4X mode. While AGP4X mode's actual transfer rate isn't significantly higher than that of AGP2X, it's still a waste not to use the mode when it's available. So, if you own an AGP4X card, it's recommended that you enable AGP4X mode for better AGP performance. Leave it as disabled only if you have a graphics card that can only support AGP1X or AGP2X transfer modes.
This BIOS function allows you to adjust the control of the AGP driving force. It is usually set to Auto by default, thereby allowing the chipset to assume control and automatically adjust the AGP driving force to suit the installed AGP card.
However, for troubleshooting or overclocking purposes, you can set the AGP Driving Control to manual so that you can select the AGP Driving Value you want. This option is slaved to the AGP Driving Control BIOS function. If you set the AGP Driving Control to Auto, then the value you set here won't have any effect. In order for this BIOS option to work, you need to set the AGP Driving Control to Manual.
The AGP Driving Value determines the signal strength of the AGP bus. The higher the value, the stronger the signal. The range of Hex values (00 to FF) translates into 0 to 255 in decimal values. By default, the AGP Driving Value is set to DA (218) but if you are using an AGP card based on the NVIDIA GeForce2 line of GPUs, then it's recommended that you set the AGP Driving Value to the higher value of EA (234). Due to the nature of this BIOS option, it's possible to use it as an aid in overclocking the AGP bus. The AGP bus is sensitive to overclocking, especially in AGP4X mode and with sidebanding enabled. As such, a higher AGP Driving Value may be just what you need to overclock the AGP higher than normally possible. By raising the signal strength of the AGP bus, you can improve its stability at overclocked speeds. But be very, very circumspect when you increase the AGP Driving Value on an overclocked AGP bus as your AGP card may be irreversibly damaged in the process!
Bank 0/1, 2/3, 4/5 DRAM timing
Use this to set the DRAM memory module timing. Most BIOSes default to 10ns. Other options available may be (from my BIOS) 8ns, Normal, Medium, Fast, Turbo. Selecting a different setting may improve RAM performance, but reduce stability. Turbo is the fastest setting, 10ns is the slowest (& most stable).
With the VIA Apollo 133 based motherboards you have the option to change SDRAM speed. Settings available are Host CLK or +/-33. Host CLK allows the SDRAM to run at the same speed as the Ext. Clock (FSB). You can use the +/-33 in case you want to run the RAM slower/faster than the Ext. Clock, e.g. If you Ext. Clock is 100Mhz you could use +33 to allow your SDRAM to run at 133Mhz. Which is a great option for those of you with PC 133 SDRAM. Or alternatively you could run at a 133Mhz Ext. Clock while your RAM runs at 100Mhz by using the -33 setting. Or you could run PC133 RAM at 133Mhz on a 133Mhz Ext. Clock (aka FSB) by using the Host CLK option. As you can see this option allows for a great deal of possibilities.
Setting this to Enabled should improve performance on graphics cards that supports it, e.g. GeForce cards. Although for most users it adversely affects performance. So I'd recommend you try both Enabled & Disabled to decide. Only try this if your graphics cards support Fast writes. If it doesn't leave it Disabled.
This allows the BIOS to check memory is parity/ECC module or not. Setting this to disabled should improve performance. Enabled may improve stability at the cost of performance.
If your motherboard has a built-in soundcard, such as the Abit VT6X4, you may choose to disable this if you want to use your own one instead. Disable it if so.
If your motherboard has a built-in videocard, you may choose to disable this if you want to use your own one instead. Disable it if so.
PCI Concurrency (Concurrent PCI/Host)
When Enabled more than 1 PCI device can be active at a time. This involves enabling extra read/write buffering. The PCI bus can also obtain access cycles for small data transfers without the delays caused by renegotiatiating bus access for each part of the transfer, so is meant to improve performance & consistency. Leave it enabled to improve performance.
PCI master 0 WS write
When enabled no (zero) wait states are used when writing to the PCI bus. When disabled 1 wait state is used. For optimal performance set this to enabled. For improved stability set it to disabled.
A high number will increase performance of the system's SDRAM. Decrease this if stability is affected.
BIOS INTEGRATED PERIPHERALS
Leave this set to Enabled. NOTE - DMA has vastly higher data transfer rates than PIO mode does. If you are not attaching any IDE devices to this port (or if you are using a SCSI / external IDE card instead), you can disable this IDE channel to free an IRQ for other use.
This option enables you to activate/inactivate the second IDE channel of the motherboard's onboard IDE controller. You should leave this enabled if you are using this onboard IDE channel. Disabling it will prevent the IDE devices attached to this channel from functioning at all. If you are not attaching any IDE devices to this port (or if you are using a SCSI / external IDE card instead), you can disable this IDE channel to free an IRQ for other use.
Use this to set the PIO mode (0 - 4) data transfer rate for the master drive. The PIO mode data transfer rates are; Mode 0 - 3.3MB, Mode 1 - 5.2MB, Mode 2 - 8.3MB, Mode 3 - 11.1MB, Mode 4 - 16.66MB. Normally, you should leave it as Auto and let the BIOS auto-detect the IDE drive's PIO mode. Note that overclocking the PIO transfer rate can cause loss of data.
This feature allows you to enable or disable UltraDMA support (if available) for the two IDE devices (Master and Slave drives) attached to that particular IDE channel. Normally, you should leave it as Auto and let the BIOS auto-detect if the drive supports UltraDMA. If it does, the proper UltraDMA transfer mode will be enabled for that drive, allowing it to burst data at up to 100MB/s. You should only disable it for troubleshooting purposes. Note that setting this to Auto does not enable UltraDMA or any of the slower DMA mode for IDE devices that do not support UltraDMA. Also, in order for any of those DMA modes to work (including the UltraDMA modes), you will have to enable DMA transfer via the OS. In Win9x, that can be done by ticking the DMA checkbox in the properties sheet of that IDE drive.
Ultra DMA-66/100 IDE controller
This option allows you to enable or disable the extra onboard UltraDMA 66/100 controller (if available). This does not include the built-in IDE controller of the Intel ICH1 and ICH2 or VIA chipsets which already support UltraDMA 66/100. This function is only for the extra IDE controller (from HighPoint or Promise) that has been included onboard the motherboard, in addition to the built-in IDE controller of the chipset. If you have one or more IDE devices attached to this UltraDMA 66/100 controller, you should enable this function in order to be able to use those IDE devices. You should only disable it for the following reasons :-
If you don't have any IDE device attached to the additional UltraDMA 66/100 controller your motherboard doesn't have an extra UltraDMA 66/100 controller onboard for troubleshooting purposes. Note that disabling this function may cut down booting time. This is because the IDE controller's BIOS won't be loaded and thus there won't be a need to wait for it to query for IDE devices on its IDE channels. So, if you don't use it, it might be best to disable it.
If you use USB devices then you'll need to leave this enabled. Otherwise disable it, you'll free up an IRQ in the process too.
This function enables or disables support for a USB keyboard. Enable it if you are using a USB keyboard. Otherwise, disable it.
This option determines whether the USB keyboard is supported via the operating system or the BIOS. Support via OS offers better functionality but at the expense of zero functionality in DOS. So, if you use real mode DOS, set the option to BIOS so that you can use the USB keyboard in DOS without the need to install a driver.
If you have only 1 graphics card in your system this can be ignored. If you have multiple graphics cards in your system, select either PCI or AGP depending on which one you want to use. This is useful for those of you who have motherboards with graphics cards soldered into the motherboard. If you only use an AGP graphics card, then setting Init Display First to AGP may reduce boot-up time a little.
This function allows you to adjust the keyboard clock for better response or to fix a keyboard problem. You should set it to 16MHz for a better response time. But if the keyboard becomes erratic or fails to initialize, try a lower clockspeed to fix that.
This function allows you to set the method by which your system can be turned on. Normally, it should be set as Button Only so that your system will only start up if you use the button/switch on the casing. Other alternative options including starting up the system using the keyboard (if it supports the Keyboard 98 standard), a keyboard hot key (for other standard keyboards) or the mouse. Note that only PS/2 mice support this function and then, not all of them. Some PS/2 mice cannot support this function due to some compatibility problem. Mice using the COM port and the USB connection will also not work with this function.
The Keyboard 98 option will only work if you have installed Windows 98 and you have the appropriate keyboard. Then you can use the keyboard's wake-up key to start up the system. Older keyboards that don't have the special wake-up key can use the Hot Key option instead. There are twelve hot keys available : Ctrl-F1 to Ctrl-F12. Select the hot key you want and you will be able to start up the computer using that hot key. However, if your keyboard is too old, this function may not work. There is no performance advantage in choosing any one of the options above so choose one that you are comfortable with.
If you use FDD's (Floppy Disk Drives) then you'll need to have this enabled. Set to disabled to save an IRQ.
Use this to set/disable/change the address for Serial port 1. You can manually select an address for it, e.g. 3E8/IRQ4, disable it altogether or set it to Auto. I'd recommend leaving it set to Auto.
This feature is usually found under the Onboard Serial Port 2 option. It's linked to the 2nd serial port so if you disable the 2nd serial port, this feature will disappear from the screen or appear grayed out. There are two different IR (Infra-Red) modes. Choose the one appropriate for the connection to the external device. Note that this feature requires an IR connector to be plugged into the IR header provided on the motherboard.
This feature is usually found under the Onboard Serial Port 2 option. It's linked to the 2nd serial port so if you disable the 2nd serial port, this feature will disappear from the screen or appear grayed out. This feature allows you to determine the transmission mode of the IR port. Selecting Full-Duplex will permit simultaneous two-way transmission, like a conversation over the phone. However, selecting Half-Duplex permits transmission in one direction at any one time only. Thus, the Full-Duplex mode is faster and much more desirable. However, consult your IR peripheral's manual to determine if Full-Duplex is supported or not.
This feature is usually found under the Onboard Serial Port 2 option. It's linked to the 2nd serial port so if you disable the 2nd serial port, this feature will disappear from the screen or appear grayed out. This feature enables you to set the IR reception/transmission polarity as High or Low. You'll need to consult your IR peripheral's documentation to determine the correct polarity.
Sets the address for the parallel port to use. Leave it at the default setting unless you need to change it to fix a resource conflict.
Use this to select the operation mode for the Parallel Port. You may need to check your motherboard manual to find this out. ECP mode being the best. Depending on your choice one of the following submenus may become available. For those who don't know what mode to select but at least know that their parallel port device supports bidirectional transfers, the BIOS offers the ECP+EPP mode. If you select this mode, then the parallel port device will be able to use either one of those modes. However, this should be considered as a last resort as you may be needlessly tying up an IRQ for nothing (if your device does not use ECP at all) or your BIOS may not select the best parallel port mode for the device. If possible, set the parallel port to the transfer mode that best suits your parallel port device.
You can use this feature to select the DMA channel of your preference. Normally, the default value of DMA Channel 3 will work just fine. You should only select the alternative value of Channel 1 if there's a conflict with another device.
This feature is usually found under the Parallel Port Mode option. It's linked to that option so if you did not enable either the EPP or ECP+EPP mode, this feature will disappear from the screen or appear grayed out. You can use this feature to choose which version of EPP to use. I couldn't find anything on the difference between version 1.7 and 1.9 but an educated guess would be that version 1.9 would be faster/better than version 1.7. So, for want of better information, I can only recommend that you select EPP 1.9 if possible but step down to EPP 1.7 if your device appears to be having some problem with the connection.
BIOS PNP/PCI CONFIGURATION
Set it to Yes to to allow your Plug & play compatible operating system, e.g. Windows 98, to manage resources. Setting it to No will let the BIOS handle this.
Force Update ESCD / Reset Configuration Data
ESCD (Extended System Configuration Data) is a feature of the Plug & Play BIOS that stores the IRQ, DMA, I/O and memory configurations of all the ISA, PCI and AGP cards in the system (PnP or otherwise). Normally, you should leave the setting as Disabled. But if you have installed a new add-on card and the consequent system reconfiguration causes a serious conflict of resources (the OS may not boot as a result), then you should enable it so that the BIOS will reset and reconfigure the settings for all PnP cards in the system during bootup. The BIOS will automatically reset the setting to Disabled the next time you boot.
Most users should let this be set at Auto. You should only set it to manual if you need to reconfigure your IRQ/DMA settings.
Assign IRQ For VGA
Many high-end graphics accelerator cards now require an IRQ to function properly. Disabling this feature with such cards will cause improper operation and/or poor performance. Thus, it's best to make sure you enable this feature if you are having problems with your graphics accelerator card. However, some low-end cards don't need an IRQ to run normally. Check your graphics card's documentation (manual). If it states that the card does not require an IRQ, then you can disable this feature to release an IRQ for other uses. When in doubt, it's best to leave it enabled unless you really need the IRQ.
If you're not using any USB hardware then you can safely disable this & free up an IRQ. If you are using USB hardware then leave this enabled.
This is a rarely seen BIOS feature that allows you to set the method by which the IRQs for your PCI cards are activated / triggered. ISA and old PCI cards are Edge triggered (using a single voltage) while newer PCI and AGP cards are Level triggered (using multiple voltage levels). When PCI devices were just introduced, the setting that everyone was asked to use was Edge because no PCI device back then supported IRQ sharing. However, now that almost every PCI device supports IRQ sharing and IRQs are usually in shortage, it's best to set it as Level so that your PCI devices can share IRQs. So, set it to Level unless you are using old edge-triggered PCI cards.
PIRQ_0 use IRQ No. PIRQ 3 Use IRQ No
Normally, you should just leave it as auto. This feature allows you to manually set the IRQ for a particular device installed on the AGP and PCI bus. This is especially useful when you are transferring a hard disk from one computer to another; and you don't want to reinstall your OS to redetect the IRQ settings. So, by specifying the IRQ for the devices to fit the original settings, you can circumvent a lot of configuration problems after installing the hard disk in a new system.
Notes :-
If you specify a particular IRQ here, you can't specify the same IRQ for the ISA bus. If you do, you will cause a hardware conflict.
Each PCI slot is capable of activating up to 4 interrupts - INT A, INT B, INT C and INT D
The AGP slot is capable of activating up to 2 interrupts - INT A and INT B
Normally, each slot is allocated INT A. The other interrupts are there as reserves in case the PCI/AGP device requires more than one IRQ or if the IRQ requested has been used up.
The AGP slot and PCI slot #1 share the same IRQs
PCI slot #4 and #5 share the same IRQs
USB uses PIRQ_4
SOFTMENU 2/3 OVERCLOCKING SETTINGS
The following BIOS settings may help you to overclock your CPU. Obviously this can potentially damage your system so be careful. The settings below are from my VT6X4's (Softmenu 2) bios, so don't worry if you don't have some of these settings. Before you even consider overclocking you need cooling & ideally lots of it. You should consider purchasing a good cooling device.
This can only be used at 66 & 100Mhz FSB's. This increases the FSB to 68.5 or 103Mhz respectively, depending on what your current FSB is. Essentially its a "safe" overclock, but disable it if it causes problems (unlikely).
Depending on your CPU, your bus speed will generally either be 66, 100 or 133Mhz. The PCI bus operates at a fraction of this, 33Mhz. By increasing the FSB you will also be increasing your PCI bus speed, which can be dangerous & devices may not work properly or your system will become more unstable. The list below shows different Ext. Clock speeds, PCI multiplier & the resulting PCI bus speeds.
66Mhz (1/2) 33Mhz
75Mhz (1/2) 37Mhz
83Mhz (1/2) 41Mhz
100Mhz (1/3) 33Mhz
103Mhz (1/3) 34Mhz
105Mhz (1/3) 35Mhz
110Mhz (1/3) 36Mhz
112Mhz (1/3) 37Mhz
115Mhz (1/3) 38Mhz
120Mhz (1/3) 40Mhz
124Mhz (1/3) 41Mhz
133Mhz (1/3) or (1/4)* 44 or 33*Mhz
0Mhz (1/3) or (1/4)* 46 or 35*Mhz
150Mhz (1/3) or (1/4)* 50 or 37*Mhz
Depending on your motherboard you may have the 1/4 multiplier for the PCI bus when 133Mhz Ext. Clock speed is reached. This will drop the PCI bus back to the standard 33Mhz (133*1/4 = 33).
CPU's nowadays are multiplier locked. So this section is pretty much for informational purposes only. To get CPU speed you need to multiply Multiplier by Ext. Clock, e.g. If the multiplier is 4.5 & Ext. Clock is 133 then the CPU speed = 4.5*133 = 598Mhz.
When the CPU speed setting is wrong & this is enabled, the system will hold. I'd recommend leaving this set to Disabled. This will of course make overclocking awkward so there's no real reason to enable it.
When overclocking, increasing the value for the core voltage may help you attain higher speeds stabily. This will increase heat too though. Don't increase voltage too much however as you may damage your processor.
Increasing this "might" help to get some of your hardware to run at higher bus speeds, try increasing the value if you experience such difficulties when overclocking your system. Some older motherboards may require you to do this even when not overclocking as they don't supply enough power for, say your graphics card.
Depending on your CPU, your bus speed will generally either be 66, 100 or 133Mhz. The AGP bus operates at a fraction of this, 66Mhz. By increasing the FSB you will be increasing your AGP bus speed, which can be dangerous & your AGP card may not work properly. Depending on your BIOS you may be able to select different AGP multipliers (1/1, 2/3 or 1/2). This may help you keep stable while overclocked. The list below shows different bus speeds, AGP multipliers & the resulting AGP bus speeds. Remember, 66Mhz is what it's intended to be.
66Mhz (1/1) 66Mhz
75Mhz (1/1) 75Mhz
83Mhz (1/1) or (2/3)* 83 or 55*Mhz
100Mhz (2/3) 66Mhz
103Mhz (2/3) 68Mhz
105Mhz (2/3) 70Mhz
110Mhz (2/3) 73Mhz
112Mhz (2/3) 75Mhz
115Mhz (2/3) 76Mhz
120Mhz (2/3) 80Mhz
124Mhz (2/3) 83Mhz
133Mhz (2/3) or (1/2)* 89 or 66*Mhz
140Mhz (2/3) or (1/2)* 93 or 70*Mhz
150Mhz (2/3) or (1/2)* 100 or 75*Mhz
The 1/2 AGP multiplier is not available on BX based motherboards, only newer ones such as the i840 or VIA Apollo 133 based motherboards. If you haven't the ability to change your bus speed via the BIOS you can always use SoftFSB to do so. The tables above showing the effects of non-standard bus speeds still applys however.
Use this option to reset your BIOS settings to the system defaults. You should only use this if you are encountering serious problems though.
Use this option to load optimized BIOS settings for your system. This option is available on the VT6X4. Although it is preferable to see what actually gets changed by making the BIOS changes yourself.
Use this to set the password that is needed to either enter into the BIOS or to boot the system. If you are the only user of your system you should leave this alone. Entering in a blank field will disable the password.
Select this option to save any changes you have made in the BIOS & exit the BIOS to load up Windows, or other operating system.
Use this option instead of the one above if you wish to exit the BIOS without saving the changes you have made.
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