This may be a none issue but I was hoping to get some suggestions. I just installed XP pro on my two year old home-built( asus a7n8x deluxe, amd 3000+, radeon 9800pro, 1gig pc3200) and have suffered a loss of game performance. I have seen about a 20% decrease in benchmarks. I moved from win2k with the same hardware. I have been wrestling with this all day and this is what I know.

Tried both ATI and Omega drivers(latest).
Have killed as many services as I dare, in win2k I had 8.
Checked ide channels to make sure they are in DMA mode.
Drives were defragged after install.
All updates are done.

The one thing I have found is that Smartgart in the ATI utilities will not let me use my AGP multiplier. If I try to change it tells me the system is unstable and sets it back to 0. I have checked the bios and AGP is enabled along with AGP fast-write. Here's the rub, I haven't noticed a difference in gaming ( Doom3 and Half-life2). Can ATI be reporting my AGP setting incorrectly? Thank you for your help.