I have a Zalman VF1000 + Thermalright Chill Factor which works pretty well. The fan at low speeds keeps the card at about 40C, and under load it gets up to 50C at 690MHz core, 975MHz memory. I just re-seated the cooler with Arctic Silver 5, added Thermalright PWN heatsinks over the 'FETs and over the last couple of days my max stable overclock has actually gone DOWN! I don't know if the card is just aging, but now when I play Counterstrike: Source at 1680x1050, max settings, 16x anisotropic filtering, 8x AA, it hangs after about 3-5 minutes. Now, my max stable overclock is 680MHz core, 975MHz RAM.

I am really rather disappointed with my max stable overclock. It seems low for how cool the card is. I was thinking of flashing the voltmod BIOS, but if I hang after 5 mins of gameplay that indicates that heat is limiting my overclock, and I don't know if more voltage is a good idea.