Nvidia 6800 gt artifacting problems

Ok here is the deal. I have a Nvidia 6800 GT. Most of the time it is
overclocked. I would say at 380/100. Standard is 350/100 which is not
much. So lately while playing recent video games such as call of duty,
doom 3, CS:CZ. I've been getting some really weird graphical issues.
Little specs of artifacting. Little to much at one time. I have
recently uploaded the hell that is SP2 for XP. I am wondering what I
can do to fix things. Here are my specs

P4 3.0 Ghz
1gig DDR-ram
asus p4p800-E
2 HD
1 DVD+/- burner
1 DVD-Rom

1)Now here is what I think. Does Nvidia need to update the drivers
because of the effects of SP2 with my card. 2) So i need a more
powerful power supply. I have a 350W right now which from looking
online is just not enough. 3)Do I need to buy that Arctic Cooling VGA
Cooler Model "NV silencer 5" to replace the **** fan that is one the
6800 GT right now. 4)Lastly I am getting weird power surges from my
house. and being the stupid person that I am right now. I do not have
a proper power supply to combat the surges. Which I am sure may
account for something. Any info or webpages would be of great help in
dealing with these issues. It's just annoying when you drop 400+ plus
for these things and it's starting to biff on you. By the way it's
only 2 months old. I have the latest drivers for everything. Did I
mention that I think SP2 is a sick joke from Microsoft!

thanks again