ATI Mobility Radeon HD 5850 Mac Edition 's Advantages
Lower TDP (30W vs 75W)
AMD Radeon R9 M390X 's Advantages
Released 5 years and 4 months late
More VRAM (4GB vs 1024GB)
Larger VRAM bandwidth (160.0GB/s vs 64.00GB/s)
1248 additional rendering cores