The recipe: Take two of the fastest GPUs on the planet capable of running DirectX 11, specially chosen for their low voltage leakage. Toss in two gigabytes of high-speed GDDR5 memory. Mix all ingredients into a card with high-end Japanese solid capacitors and a souped-up thermal dissipation system. The result: the XFX Radeon HD 5970—a GPU so yummy, you may even go back for seconds.While the product name doesn’t hint at the card’s dual-GPU nature, there’s no mistaking the presence of two graphics chips when you check out the back of the board. Then there’s the sheer size of it: At more than 12 inches, you’ll need a high-end PC case that’s deep enough to handle this monster. You’ll need a beefy power supply, too, since the HD 5970 burns 294W at full throttle—and that’s if you don’t overclock it. The good news is the card consumes just 42W at idle, less than double the idle power of a single HD 5870, thanks to an enhanced deep-sleep mode for the slave GPU.