NVIDIA GeForce GTX 680 Mac Edition 's Advantages
Larger VRAM bandwidth (192.3GB/s vs 96.00GB/s)
896 additional rendering cores
AMD Radeon RX 550 640SP 's Advantages
Released 4 years and 6 months late
Boost Clock has increased by 1% (1071MHz vs 1058MHz)
Lower TDP (60W vs 195W)