NVIDIA GeForce GTX 680M 's Advantages
More VRAM (4GB vs 2GB)
Larger VRAM bandwidth (115.2GB/s vs 28.80GB/s)
960 additional rendering cores
AMD Radeon R7 M270 's Advantages
Released 1 years and 7 months late
Boost Clock has increased by 9% (825MHz vs 758MHz)