AMD Radeon R9 M385X 's Advantages
More VRAM (4GB vs 2GB)
Larger VRAM bandwidth (76.80GB/s vs 48.00GB/s)
384 additional rendering cores
AMD Radeon 540 Mobile 's Advantages
Released 3 years and 10 months late
Boost Clock has increased by 2% (1124MHz vs 1100MHz)