BIOS Tweaks for a Speedier PC

BIOS settings play an important role in speeding up your computer. They can be quite cryptic, and therefore need a bit of understanding before you can play around with them. Plus, since there are so many different versions of BIOS, your PC may not have some of the settings we are about to discuss. However, you should be able to do most of what we suggest. If your PC refuses to boot up after you’ve made some changes, then you may have to reset the BIOS (see Reset your BIOS, page 56).

• Set the AGP bus speed to 4x. The AGP bus originally ran at 1x, but as newer video cards were released it was upgraded to 2x and then recently to 4x. If you have a video card that needs a 4x bus, performance will be crippled at 2x.

• Enable the Video ROM BIOS Shadow option under Shadowing options. It speeds up your computer by copying the contents of your video BIOS code from the slow ROM on which it resides to faster RAM.

• Enable L1 and L2 caches of the processor, and disable ECC checking. ECC checking can take a little overhead without significant advantage.

• If you use onboard graphics, assign as much memory to the Shared VGA Memory as possible, but make sure you have enough RAM on your system as well. For example, if you have 128 MB RAM, 16 MB could be used as video memory and rest as system memory.

• Reduce CAS (Column Access Strobe) latency. CAS latency refers to the delay that occurs when accessing the column part of a memory address (looking at computer memory as a spreadsheet). Usually the delay is 2 to 3 cycles, depending upon your RAM speed. Most memory modules support both 2 and 3, but usually default to 3. So reducing this from 3 to 2 can result in some performance gain. However, this particular setting should be done with care, as it can crash your computer, in case your RAM doesn’t support both. If this happens, then change the setting back to 3.

• Besides these, there are certain other options you could play around with. For instance, if you have any ports on your PC, which you don’t use, then disable them from the BIOS. For instance, if you don’t have a printer, then disable the parallel port. Another option is to disable the ‘Spread Spectrum Control’ option. Enable ‘PCI to DRAM’ prefetch and ‘Fast Write’ under AGP options. The latter speeds up AGP access. Power saving should be enabled for those who are concerned about power consump- tion, but performance freaks should disable it.

Note: These settings are under different menus depending upon your BIOS version.