NVIDIA GeForce GTX 680MX Mac Edition 's Advantages
Released 9 months late
More VRAM (2GB vs 1024GB)
Larger VRAM bandwidth (160.0GB/s vs 14.40GB/s)
1136 additional rendering cores
AMD Radeon HD 7550M 's Advantages
Boost Clock550MHz
Lower TDP (14W vs 122W)