ABIT KR7A BIOS Settings

The table below shows the BIOS settings I am using on the ABIT KR7A-133 motherboard. My ABIT KR7A-133 BIOS version is B5, dated 10/3/2002. Italics indicate values that are not updateable, although they might be under different BIOS settings.

This BIOS optimization guide available from Adrian’s Rojak Pot is an excellent general-purpose source for information on BIOS settings.

SoftMenu III Setup

Parameter	Setting	Comments
CPU Operating Speed	1800+(133)
CPU FSB Clock (MHz)	133
Ratio (FSB:AGP:PCI)	4:2:1
Multiplier Factor	x11.5
Speed Error Hold	Disabled
CPU Power Supply	CPU Default
Core Voltage	1.750v
I/O Voltage	3.50v
DDR Voltage	2.55v
DQ Control	Center DQ
CPU Fast Command Decode	Fast	This setting will give a performance improvement over Normal and is safe with the high-quality components I’m using. The Ultra setting makes little performance difference and isn’t worth the risk of causing instability.

Standard CMOS Features

Parameter	Setting	Comments
IDE Primary Master	IC35L080AVVA07-0	This is the IBM 120GXP 80GB hard drive. The hard drive and CD-ROM should not be on the same IDE since doing so will cause them both to run at the speed of the slower device. The CD-ROM is much slower than the hard drive. Placing them on separate IDEs allows them to both run at their maximum speeds.
		IDE Primary Master (sub-menu)
		Parameter Setting Comments IDE Primary Master Auto - Access Mode Auto
IDE Primary Slave	None
IDE Secondary Master	LTN525D	This is the Lite-On 52x CD-ROM.
IDE Secondary Slave	None
Drive A	1.44M, 3.5 in	This is the floppy drive.
Drive B	None
Floppy 3 Mode Support	Disabled	Floppy 3 is the Japanese standard floppy drive mode. It stores 1.2MB on a 3.5″ diskette instead of 1.44MB.
Video	EGA/VGA
Halt On	All, But Keyboard	Halt on all errors except Keyboard Absent error. This enables the machine to boot without the keyboard plugged in.
Base Memory	640K	DOS device drivers, TSRs and any programs to be run, plus their data.
Extended Memory	523264K	Memory above 1 MB is known as extended memory, and is not normally usable under DOS.
Total Memory	524288K	Base + Upper + Extended = Total Memory.

Advanced BIOS Features

Parameter	Setting	Comments
Virus warning	Disabled	Symantec Norton Antivirus protects My Super PC.
CPU L2 Cache ECC Checking	Enabled	Improves stability and reliability with no real impact to performance.
Quick Power On Self Test	Enabled	Skip Power On Self-Tests for faster boot.
First Boot Device	CDROM	Normally this should be set to HDD-0 to boot directly from the hard drive, but set it to the CDROM for now since that’s how we’ll need it when we’re ready for the step after configuring the BIOS parameters. When it’s set to HDD-0 the computer does not look to see if there’s a floppy disk in the floppy drive from which it should boot. Set this to Floppy for disaster recovery procedures.
Second Boot Device	CDROM	Normally this would be set to HDD-0 since the First Boot Device is the only boot device.
Third Boot Device	CDROM	Ditto.
Boot Other Device	Disabled	Gives the “ok” for the BIOS to try the Second Boot Device and Third Boot Device if the First Boot Device is a “no-go”, but My Super PC just boots from the First Boot Device, which is the hard drive so - Disabled.
Swap Floppy Drive	Disabled	I’ve only got one floppy drive, so it’s going to be A:.
Boot Up Floppy Seek	Disabled	Skipping this check makes the boot go a bit faster.
Boot Up NumLock Status	Off	This item is a matter of personal taste.
Typematic Rate Setting	Enabled
Typematic Rate (Chars/Sec)	30	6, 8, 10, 12, 15, 20, 24, 30
Typematic Delay (Msec)	250	250, 500, 750, 1000. This is the delay, in milliseconds, before the keyboard automatically repeats the keystroke that you have pressed continuously.
Security Option	Setup	If you have set a password, select whether the password is required every time the System boots, or only when you enter Setup. I don’t even have a password set, so it’s a moot point.
APIC Mode	Disabled	Setting to Enabled can cause instabilities. Once the operating system is installed, such as Windows XP in my case, this setting cannot be changed without reinstalling the operating system, regardless of whether the initial setting is Disabled or Enabled. The purpose of setting it to Enabled is to extend the number of IRQ’s, which sounds like a real risky proposition. I’m not surprised to see the conclusion reached at APIC: Benefit or Trouble. The number of IRQ’s should be fine without being extended, anyway.
MPS Version Control For OS	1.1	Not changeable with APIC Mode set to Disabled.
OS Select For DRAM > 64MB	Non-OS2	IBM’s relic.
Report No FDD For WIN 95	No	When using Windows 95 without a floppy drive, set to Yes. Say - how many ABIT KR7A-133 motherboards do you suppose are out there running under Windows 95 without a floppy drive?
Video BIOS Shadow	Disabled	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 as it will speed up VGA BIOS (C0000-C7FFF) accesses.
Delay for IDE Initial (Secs)	0	Certain hard disk drives require some extra time to spin up in a cold boot. If the system does not start after the memory tes t, try adding time in this field.
Small Logo(EPA) Show	Disabled

Advanced Chipset Features

Parameter	Setting	Comments
		DRAM Clock/Drive Control (sub-menu)
		Parameter Setting Comments DRAM Clock 133 MHz DRAM Timing Manual DRAM CAS Latency 2 Although the memory is spec’d at 2.5, Crucial memory is high quality and will run at the faster 2 setting. Bank Interleave 4 bank For best performance. Precharge to Active(Trp) 2T Active to Precharge(Tras) 6T This value is recommended for PC2100 memory to improve stability with no real loss of performance. A value of 5T is recommended for PC1600 memory and a value of 7T is recommended for PC2700 memory (which the ABIT KR7A-133 doesn’t support anyway). Active to CMD(Trcd) 2T DDR DQS Input Delay Auto Input Delay Value 24 DDR DQS Output Delay Auto Ouput Delay Value 40 Command Drive Strength Hi Set this to Hi for added stability, especially with multiple DIMM’s in use. Rx6C OverWrite Disabled Default value. Even ABIT technical support couldn’t tell me what this does, so it’s best to leave it alone. OverWrite Rx6C 00 Ignored since Rx6C OverWrite, whatever that is, is disabled. Rx6D OverWrite Disabled Default value. Even ABIT technical support couldn’t tell me what this does, so it’s best to leave it alone. OverWrite Rx6D 0A Ignored since Rx6D OverWrite, whatever that is, is disabled. DRAM Queue Depth 4 level For best performance. DRAM Command Rate 2T Command The 1T Command setting is unstable and problematical. DCLK Feedback Delay 0 ps The only agreed safe value.
		AGP & P2P Bridge Control (sub-menu)
		Parameter Setting Comments AGP Aperture Size 64MB The BIOS optimization guide reference from Adrian’s Rojak Pot above provides a great description of how this should be set and why. A value of 64MB is best for most configurations. AGP Mode 4x AGP Driving Control Auto Setting to Manual may destabilizes the video card. AGP Driving Value DA Not changeable with AGP Driving Control set to Auto. AGP Fast Write Enabled AGP Read Synchronization Disabled Setting to Enabled may cause instability. AGP Master 1 WS Write Enabled By default, the AGP busmastering device waits for at least 2 wait states before it starts a write transaction. This option sets the delay to 1 wait state. This setting works fine with the motherboard and video card I have in My Super PC. But if you see anything strange with your graphics then set back to Disable and see if it clears up. AGP Master 1 WS Read Enabled Default is at least 2 wait states. The Comments under AGP Master 1 WS Write apply.
		CPU & PCI Bus Control (sub-menu)
		Parameter Setting Comments PCI Master Read Caching Disabled Setting to Enabled allows CPU L2 cache to be used for PCI master reads, but that leaves less CPU L2 cache for system memory which doesn’t sound like a good trade, so I’ve set it to Disabled. PCI Master Bus Time-Out Disabled Default value. If a PCI device is troublesome, like crackling noises are coming from the PCI sound card, then changing this parameter may clear it up. PCI Master Priority Rotation Co Disabled Controls the CPU’s access to the PCI . The default value is Disabled. As long as the PCI devices are performing properly it’s fine to leave it disabled. By the way, it looks like the full name of the parameter was overwritten on the display by it’s displayed value. PCI1 Master 0 WS Write Enabled Performance is better when set to Enabled. PCI2 Master 0 WS Write Enabled Ditto. PCI1 Post Write Enabled Ditto. PCI2 Post Write Enabled Ditto. PCI Delay Transaction Enabled 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. Master Delay Transaction Disabled Default value. Even ABIT technical support couldn’t tell me what this does, so it’s best to leave it alone.
Memory Hole	Disabled	Some special ISA cards require this area of memory for them to work properly. Enabling this function reserves the memory area for the card’s use. It will also prevent the system from accessing memory above 16MB. This means that 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.
System BIOS Cacheable	Disabled	This feature is only valid when the system BIOS (F0000-FFFFF) is shadowed. It greatly speeds up accesses to the system BIOS. However, this does not translate into much better system performance because the OS does not need to access the system BIOS much. As such, it would be a waste of L2 cache bandwidth to cache the system BIOS instead of data that are more critical to the system’s performance. In addition, if any program writes into this memory area, it will result in a system crash.
Video RAM Cacheable	Disabled	Set to Disabled for all nVidia based cards.

Integrated Peripherals

Parameter	Setting	Comments
		VIA OnChip IDE Device (sub-menu)
		Parameter Setting Comments IDE Prefetch Mode Enabled For best performance. Onboard IDE-1 Controller Enabled These are the ATA/133 IDE controllers. Onboard IDE-2 Controller Enabled These are the ATA/133 IDE controllers. - Master Drive PIO Mode Auto Set all of these to Auto and let the BIOS determine if each drive is capable of DMA support, and its respective PIO mode. - Slave Drive PIO mode Auto Ditto. - Master Drive Ultra DMA Auto Ditto. - Slave Drive Ultra DMA d> Auto Ditto.
		SuperIO Device (sub-menu)
		Parameter Setting Comments Onboard FDD Controller Enabled I do have floppy. Onboard Serial Port 1 3F8/IRQ4 Standard. Onboard Serial Port 2 2F8/IRQ3 Standard. - Onboard IR Function Disabled No Infra-Red devices. - RxD , TxD Active Hi,Lo Not applicable since IR is disabled. - IR Transmission Delay Enabled Not applicable since IR is disabled. - IR Function Duplex Half Not applicable since IR is disabled. - Use IR Pins IR-Rx2Tx2 Not applicable since IR is disabled. Onboard Parallel Port 378/IRQ7 Standard. - Parallel Port Type SPP Set this to SPP unless you have a device or printer that specifically requires use of ECP/EPP modes such as a parallel port scanner, zip drive, etc.” - EPP Type Select EPP1.9 Not changeable since Parallel Port Type is set to SPP. - ECP Mode Use DMA 3 Ditto.
Init Display First	AGP	Set to AGP if your primary display is your AGP adapter, or to PCI if the primary display is a PCI video card.
USB Controller	All Enabled
- USB Keyboard Support	BIOS

Power Management Setup

Parameter	Setting	Comments
ACPI Suspend Type	S1(POS)
Power Management Option	User Define	My Super PC does not use the Suspend power saving mode.
HDD Power Down	Disable	Ditto.
Suspend Mode	Disable	Ditto.
Video Off Option	Suspend -> Off	Screen off when system is in SUSPEND mode, which it never is, in my case.
Video Off Method	DPMS Support	Use this setting if you have a PnP capable monitor.
Modem Use IRQ	NA	Manually assigning the IRQ is not needed.
Soft-Off By PWRBTN	Instant-Off	You don’t want slow death.
State After Power Failure	Off
		IRQ/Event Activity Detect (sub-menu)
		Parameter Setting Comments PS2KB Wakeup from S3/S4/S5 Disabled My Super PC awakens on pushing the power button only. Just so you know, PS2KB is the PS/2 keyboard and S3/S4/S5 are sleep states PS2MS Wakeup from S3/S4/S5 Disabled. PS2MS is the PS/2 mouse. VGA OFF LPT & COM NONE HDD & FDD OFF PCI Master OFF PowerOn by PCI Card Disabled Modem Ring Resume Disabled RTC Alarm Resume Disabled Date (of Month) 0 Not applicable with RTC Alarm Resume Disabled. Resume Time (hh:mm:ss) 23 :0 : 0 Not applicable with RTC Alarm Resume Disabled.
		IRQs Activity Monitoring (sub-menu)
		Parameter Setting Comments All interrupt Event Off Disable IRQ’s from having any effect on power management.

PnP/PCI Configurations

Parameter	Setting	Comments
PNP OS Installed	Yes	If you’re using Windows (and who isn’t?), set this to Yes.
Force Update ESCD	Disabled	Normally leave this Disabled. But if, for example, you add a new card and the subsequent system reconfiguration causes a serious conflict of resources (maybe the OS won’t boot) then setting this to Enabled is a solution to be considered.
Resources Controlled By	Auto (ESCD)	Let the BIOS figure out IRQ’s and DMA channels.
PCI/VGA Palette Snoop	Disabled	The VGA “palette” is the set of colors that are in use by the videocard when it is in 256-color mode. Since there are thousands of colors and only 256 can be used in that mode, a palette containing the current colors is used. Some special VGA cards, high-end hardware MPEG decoders, etc. need to be able to look at the video card’s VGA palette to determine what colors are currently in use. Enabling this feature turns on this palette “snoop”. This option is only very rarely needed. It should be left at “Disabled” unless a video device specifically requires the setting enabled upon installation.
Assign IRQ for VGA	Enabled	Set to Yes if you are using an AGP video card.
Assign IRQ for USB	Enabled	Set to Yes if you are using an USB device.
PIRQ_0 Use IRQ No.	Auto	The more the BIOS automatically figures out the IRQ settings the better I like it.
PIRQ_1 Use IRQ No.	Auto	Ditto.
PIRQ_2 Use IRQ No.	Auto	Ditto.
PIRQ_3 Use IRQ No.	Auto	Ditto.

PC Health Status

Parameter	Setting	Comments
Temperature Warning	Disabled
CPU Shutdown Temperature	Disabled
Shutdown when CPUFAN Fail	Disabled

© 2001-2003, Rob Williams, all rights reserved.

原文出處：http://www.build-pc.com/bios_settings.shtml