Sli with Vista x32 (x86) Problem

Hey everyone!
I just got my new computer running with Vista and I'm having problems enabling SLi.

The Device Manager shows both video cards, but one has a yellow "!" next to the icon, and the nVIDIA manager does not offer any option to enable SLi. I have a feeling that this is a driver issue. Anyone have 2 8800GTX's in Sli working on vista? If so, can you tell me what drivers your using.

My setup:
CPU: Intel QX6700 Quad Core
Motherboard: ASUS P5N32-E SLi (not the SLi Plus)
RAM: CORSAIR Dominator 2GB (2 x 1GB) DDR2 1066 (PC2 8500) (TWIN2X2048-8500C5D)
Video Cards: 2x BFG 8800GTX (Water Cooled edition) in SLi
PSU: Thermaltake Toughpower 850 watt (Quad Sli Ready)
HDD: Maxtor 350Gb Sata
Operating System: Vista x32 - Home Premium Edition

Thanks for any input!
Ian