NVIDIA Quadro K4200 's Advantages
More VRAM (4GB vs 2GB)
Larger VRAM bandwidth (172.8GB/s vs 40.10GB/s)
1088 additional rendering cores
NVIDIA Quadro P500 Mobile 's Advantages
Released 3 years and 6 months late
Boost Clock has increased by 94% (1518MHz vs 784MHz)
Lower TDP (18W vs 108W)