I bought a 8800GT to replace an aging Radeon X700 Pro. I installed the card and the newest drivers, but when I tried to enable the Aero theme, the computer stopped responding, even the mouse cursor. I have already reseated the card and made sure that the PSU is strong enough. My X700 Pro did not do this with the Aero feature enabled.

"and made sure that the PSU is strong enough" At least 400W with 26A on the +12v rail? Good quailty/brand name unit, not a generic POS?

Sounds like the card isn't getting enough voltage to run in "3D mode". The Aero GUI is Direct3D-rendered. I used to have similar problems with 3D applications on 440BX boards powering newish cards. Most of the time, I was able to get the app to run by increasing the AGP voltage. Stuff to try: -Make sure that your power supply has at least 26 amps on its 12v rail (or 17+17, if it's a dual-rail model) -Make sure that a 6-pin PCIe peripheral power cable is plugged into the card. Oh, and make sure that it's a true PCIe plug, not one of those PCIe to double Molex (hard drive power) adaptors. I've had problems with those things, especially trying to power high-end cards. If your power supply does not provide a true PCIe power cable, buy a new one. -If your motherboard has a 4-pin molex connector near the PCIe slot(s), make sure that a power cable is plugged in. These EZ_Plugs, as Asus calls them, assist in powering high-end cards and SLI configs. While my Asus manual states that the EZ_Plug is only required for SLI, it's probably best to have it plugged in--even if you don't have two videocards installed. -If all else fails, look for the PCIe voltage selector in your BIOS setup. Bump it up a notch. Homebuilt projector: Samsung 1080p panel Pixelworks controller 2 HDMI, 2 Component, 1 VGA Homebuilt enclosure 120" 16:9 screen Connected to: HTPC w/ BD, satellite receiver, XB360.

Yes! That was it, the molex on the mobo was unplugged. I didn't even know my mobo had one of those till today. Thanks so much!