AMD Radeon HD 7990 's Advantages
Larger VRAM bandwidth (288.0GB/s vs 224.4GB/s)
NVIDIA GeForce GTX 980 's Advantages
Released 1 years and 5 months late
Boost Clock has increased by 22% (1216MHz vs 1000MHz)
More VRAM (4GB vs 3GB)
Lower TDP (165W vs 375W)