Ok, I just picked up the eVGA 256-P2-N569-SG eVGA "Signature Series" GF7900 GT 600 MHz card. Under normal operation the card is realtively quiet, but when gaming, the fan comes on and is really loud. I have a fairly quiet case (Antec P180) and it's still loud enough to be annoying. I checked the temp and it's at around 61 C. Is this normal?
I could suggest the zalmann vf-700cu, it may not be heat pipe but it is all copper and also the fan is VERY quiet. I have it on my 7600gt and the temps never goes over 57°, even when oc to 625 core / 835 mem.
The KuFormula VF1 Plus is excellent as well, I wrote a review on tom's... and I've heard the Thermalright V1 Ultra is also very good. Oh yeah, and Arctic cooling's accelero X2... and evercool's turbo-2...
I've seen a plastic washer put on the screw that holds the card to the case. The idea was to help dampen simpathetic vibrations between the card and the case. It helped for that particular combination, but can't say that it would for you. Just something to think about and try if you feel like it.