Yes I keep my drivers up to date with Geforce experience, as soon as a new WHQL driver is out I update. I don't run SLI just the single GTX 580. However one of my CoH 2 mates runs SLI, but disables it before launching CoH 2, not surprisingly he gets the pink vehicles and transparent houses bugs the most often, even with SLI disabled. Don't think the drivers are to blame, because Nvidia can't do much on their end, CoH 2 is not their product, it's up to Relic to work with Nvidia on tailored drivers for a solid performance increase and an SLI profile.
Just had a couple of games last night and I did notice a solid FPS increase and overall smoothness, FPS were in the 50-60 range in 1v1s at high textures, medium image quality, low AA, high setting for Snow, high setting for physics,Ambient Occlusion at 1920x1200. Need to test some more just to rule out the placebo effect. Also need to test on 4v4s as my average FPS was 30 and as low as 15-20 when things got hectic.
So far good patch!
ok, then this relates to him and not you.
around 6 months ago NVIDIA introduced a bug with CoH2 to SLI systems that caused texture corruption. It took a couple of months but i worked with them and got it fixed so your friend can leave SLI on and it will have no negative affects, the game never used it anyway.
as for the pink, it's either a missing texture or texture corruption. i have no idea what causes it, i've seen it once or twice and not recently.