It's got two 6800GT cores, and a cooler the size of France, it's the dual 6600GT 3D1's bigger brother, from Gigabyte:
With an exact weight of 990grams, the Gigabyte GV-3D1-68GT videocard is a substantial piece of hardware. Much of that weight is the direct result of the two large gold-coloured aluminum heatsinks which are mounted on each side of the videocard with eight screws.

A single nVidia Geforce 6800GT videocard can run pretty warm when processing complex 3D graphics, and two distinct GPUs certainly make for a very intensive thermal equation. Toss in a small mountain of BGA DDR3 memory modules, and power circuitry, and we have a videocard that has a lot of heat to dissipate.
[PC Stats]