Not sure what it is, but that colors thing... well, I still get it, but not all the time. Seems if my system is being taxed pretty good, textures will start showing odd colors to them (rainbow and quite trippy). Didn't have this issue with XP. And the video restart issue is still there (30 seconds or less after joining the server for the first map only), but now it seems there's a limit to how many maps I can play before it becomes a more prominent issue (actually requiring a vid_restart command issued into the console).