In my BIOS i was just lookign around and I saw in my Frequencys and Voltages menu that a choice was "Change PCIe (bus) Frequency" I could make it 100mhz or 200mhz. I dotn have a PCIe card atm but i ordered a 8800GT and after looking through my mobo manual i still dont understand what this is for. Does it just make it faster? or does it have something to do with PCIe x16 2.0?
Do not change your PCIe bus frequency to above 101 unless you want to risk damaging your card. It will not boost video card performance but it can help with Overclocking your CPU because it relieves stress on the North bridge as opposed to setting it to "auto". Also setting it manually can prevent it from clocking higher when you overclock the Frontside bus (FSB).
^^ sort of, some ati cards (2900xt anyone?) love up to 150mhz PCI-e, and i found, wiht 2x2900s in a 975x board with the PCI-e at 150vs 100, the 150 gave me a 15% performance increase, however, unless you are in the exact same situation, i'd recommend you dont touch it