AMD Radeon HD 7970 GHz Edition 's Advantages
Boost Clock has increased by 2% (1050MHz vs 1032MHz)
More VRAM (3GB vs 2GB)
Larger VRAM bandwidth (288.0GB/s vs 144.2GB/s)
1088 additional rendering cores
NVIDIA GeForce GTX 660 's Advantages
Lower TDP (140W vs 300W)