MSI of late have been moving the way of the market, towards the overclockers. MSI uses an AMI BIOS setup (personally I prefer Award, but to each his own) with quite a few tweaking options that give you reasonable overclocking control.
Overclocking is handled under the HW monitor setup option in the BIOS. Here you will find the standard voltage, fan RPM and temperature monitors as well as the overclocking options.
First off is Clock controlled by option. You have two options. Option 1 is HW, this tells BIOS to read the FSB and multiplier data from the SRAM onboard the P4 and sets the FSB and multiplier accordingly. Option 2 is SW, when this is selected the FSB select and Multiplier select is available and you can set them accordingly.
Next we have Multiplier ratio. If your CPU is unlocked, you can adjust your multipliers of the P4. Of course finding one of theses CPU's in the retail market is like trying to find a drink of water on the Simpson desert. IF your multiplier is not adjustable, the option displays "Locked" so you will know if you can change it or not.
Below this you have three voltage control options, Vcore, DDR and AGP. Vcore allows you to set your CPU core within a certain limit. If you have a P4 based on the Willamette core, then you can adjust your CPU from default voltage up to 1.85v. If your CPU is Northwood core, 1.7v is the maximum you can select. This is somewhat limiting, but still was more than enough for us.
DDR voltage can be set at 2.5, 2.6 or 2.7v only. This is rather disturbing as DDR memory has proven to be safe up to 3.0v. These options are even more limiting if you are using DDR-266 memory to overclock. DDR-333 you should have no problems. AGP voltage is able to be set at either 1.5, 1.6 or 1.7v. This should be more than enough to supply that hungry overclocked video card all the power it needs for stable AGP bus operations.
When we did out tests, we used a P4 Willamette unlocked so we could set the multiplier back from 20x to 14x. This allowed us to overclock the FSB and memory only without the CPU being the limiting factor. We got 146MHz out of this board before we had data corruption, so unofficially you should be able to run the new 533FSB processors due out very soon.
Gigabyte in the past has been known for their OEM boards rather than those aimed at the hardcore gamer or overclockers. But all has changed recently with their AMD and P4 solutions, and the GA-8IRXP is one of their best. Using a standard Award BIOS setup, which most people feel familiar with, you can do some magnificent tweaking to the memory as well as overclock your board.
Overclocking options are located under the Frequency/Voltage Control sub-menu, and from here you have multiplier, FSB, Vcore, VDIMM, Vapg and divider control of your system.
First off is the Liner Frequency control option. When set to enabled, you can set all the overclocking options by manual. When set to disabled, the CPU SRAM is read for CPU parameters.
On the overclocking front, your first major setting is the FSB Select. Here you can set your FSB from 100MHz up to 200MHz in 1MHz steps; only the best for overclocking. Next you have Vcore setting. No matter what CPU you have, you can set the core voltage from 1.1v up to 1.85v in 0.025v steps. With the latest BIOS revision from Gigabyte, they have resolved some POST problems when setting Vcore above 1.7v. Marvelous!
VDIMM is the next option you can set. You have the option to set the DDR SDRAM voltage from 2.5v up to 3.0v in 0.1v steps for best clocking results. Next you have your AGP voltage setting. Here you can adjust settings from 1.5v up to 2.0v on 0.1v steps.
After all this you have the next two options, AGP speed and PCI speed. Here you can select a different FSB ratio, the different speeds your AGP can run at. This allows you to keep the AGP as close to specs as you can when overclocking the FSB.
In testing we used the unlocked Willamette and was able to run the FSB at 162MHz, an extremely high score. P4 533FSB looks very good for this board too.
To be honest with everyone out there, this is my very first Soyo review board, and so far I have been rather impressed with their performance, and with their overclocking. Well, let me say it's something different. Soyo incorporates the Award BIOS into their board with their own special sub-menu called "Soyo Combo". In here you will find all your specialty options as well as tweaking and overclocking.
First off in the menu you have System Speed Control option, settings are Normal and Turbo. Turbo sets DRAM and caching settings to their most aggressive, Normal allows manual control of the settings. Next is the System control option. You have two options, Auto or Manual. In Auto mode, CPU parameters are retrieved from SRAM for FSB and Multiplier. In manual you can set your parameters manually.
Next comes your FSB Gain Control. This allows you to set the FSB from 100MHz to 200MHz in 1MHz steps, a definite must. Soyo has also utilized the Mighty Bolt option, and since we explained this before, we won't repeat it. After this you get your three voltage controls. Vcore first, DDR second and AGP third. Vcore can be set from 1.1v up to 1.85v no matter that CPU you use. DDR can be set from 2.5v up to 2.78v in 0.02v steps, definitely a weird voltage control here. Same scenario with the AGP; from 1.5v up to 1.68v in 0.02v steps.
This ends your overclocking control. Basic but helpful. In our tests we only got 135MHz stable, but that is more than enough for 533FSB P4's, so no board is at a disadvantage on that front.
In all Gigabyte has the best overclocking, followed close by MSI and Soyo.