As I said in some previous posts: lower prices = less piracy= more copies sold = more revenue. It's very simple... Why Mr. Bill doesn't understand that?
This is the cause of flickering. Check the fan on the card heatsink and make sure it is running properly. Clean the dust accumulated on the blades and around them. Use a can of compressed air to blow it away. nVIDIA hasn't released Vista RTM drivers as yet, those for RC 2 should work OK. I've got a 6600GT in my rig and runs OK.
Sitting next to me right now is a friend of mine working as an electrician for the national electricity company and this is what he says: "Get a qualified electrician to inspect the wiring in the house. Urgently!"