Performance was significantly down for the GeForce 8800 GTX under Windows Vista. Approximately 22% at 1280x1024 under 32-bit Vista, and 21% when comparing the 64-bit operating systems.

The chaps over at Firing Squad look at how Vista stacks up against XP for Geforce cards and besides posting benchmarks, interviews NVIDIA about. Here's an excerpt:

Clearly NVIDIA's Windows Vista drivers still need a lot of work. Features are missing, and end users running into bugs and other issues with games and other software applications. Then there's the performance problem.

As you just saw in our performance results, NVIDIA's Vista driver performance is definitely behind that of Windows XP. In some cases it's not too bad, F.E.A.R. and Company of Heroes ran about 4-5% slower for the GeForce 8800 GTX for instance, although the margin was a little greater for the 7900 GTX under F.E.A.R. But there were also notable titles such as Half-Life 2 Lost Coast that really stood out. The 8800 GTX's performance nearly dropped in half in Lost Coast. Looking at the latest Gamespy stats, HL2 is the #2 shooter played online, trailing only the original Half-Life, so this is a pretty big deal. Battlefield 2 and BF2142 occupy the next two spots on Gamespy's list, they're both based on the same basic game engine, and the 8800 GTX saw significant performance declines under Vista in our testing with BF2142. That's definitely not good.

Based on all this, it certainly looks to us at least that NVIDIA's Vista drivers are definitely behind that of AMD, at least on the Direct3D front (we still give the nod to NVIDIA in OpenGL). Not that AMD's Vista drivers are perfect, we noted performance drops there as well, and ran into significant problems when running OpenGL, but their D3D driver is more polished overall than NVIDIA's right now. At least that's how it looks on the outside looking in.

Thankfully, NVIDIA's Dwight Diercks made it clear that NVIDIA isn't resting on this issue. We eagerly await more details on their upcoming driver release plan for Vista, and we're sure many of you do too. It's a shame though that it appears that GeForce 7 SLI owners will have to wait until March before they get a driver, and we're crossing our fingers that perhaps NVIDIA could provide a beta a little sooner.