Some trouble with it on the EVGA forums as well. For the nonce, here's a guy that thinks he has the solution:

Quote Originally Posted by JediNachos
Yeah. I had the same issue isntalling drivers in Vista too. To get around it, I uninstalled the device from device viewer.

1. Uninstall NVidia display drivers.
2. Boot to safe mode, and run driver cleaner.
3. While is safe mode, use deivice manager and uninstal the display adapter.
4. Boot normally. If Windows tries to install the driver, say cancel.
5. Install your NVidia driver
6. Boot

See if that helps.
I don't have Vista64 installed currently, but I have the disk, a blank hard drive, and an 8800GTX sitting around. I'll try the drivers out later if I have time.