Thermalright HR-03 Plus with a 92mm Vantec Silencer on top works wonders.
Dropped original temps 10C. Flashed the BIOS to BFG's 8800GTX OC2 specs, only goes up 3-5C at max settings in games like Oblivion, Supreme Commander, etc.
I honestly recommend it.
What I didn't like is I thought...