I'm using this card in rig #4 of my sig, it's an STB Velocity 4400, an original TNT card. I had ripped the heatsink off the card about a year ago to use on the northbridge of another mobo, and hadn't used the card since. I tried running without a heatsink but it got way too hot to touch within about 60 seconds. The only thing I had lying around were two alpha ramsinks... I almost only used one ramsink but I'm really glad that I used two - they get VERY HOT. I had to put an 80mm fan near the card to keep everything stable.