AMD Radeon HD 8990 OEM 's Advantages
Released 1 years and 5 months late
Boost Clock1000MHz
More VRAM (3GB vs 512GB)
Larger VRAM bandwidth (288.0GB/s vs 22.18GB/s)
1928 additional rendering cores
ATI Radeon HD 4580 's Advantages
Lower TDP (65W vs 375W)