I have to say that I'm fairly impressed. I put the DuOrb on my 1950xt, but the card ended up running hotter. I believe the card was faulty and ended up dying a few days later (still need to send it in for RMA). I got my 4850 a few days ago, and as everyone knows, they run hot as the sun. Out of the box, it was idling at 77*C. At that point I didn't even bother to put it under load, as that is way too hot for my tastes. I modded the MSI BIOS and bumped the fan settings up to 50%. After that, it idled at 61*C, but was cooking the case under load. I didn't check the temperature, but from previous experiences, it was in the 90*C range. The RAM sinks that came with the DuOrb were covered in dust from sitting for several weeks as I had forgotten to stick them in a bag. After calling around and realizing nobody sells thermal tape locally, I decided to stick the DuOrb on w/o the RAM sinks. The thermal pads from the 4850 are actually sticky, so I ended up using them to stick the RAM sinks on (1950xt stock heatsink had rubbery pads). My idle is now 37*C, and the load doesn't go over 50*C. I'm sure everyone has read plenty of aftermarket heatsink reviews, but I figured I'd post up in case anyone was hesitating pulling the trigger on one. I think it's well worth it for the peace of mind, even if ATi says the stock sink keeps everything within specs.