NVIDIA Quadro K5100M 's Advantages
Boost Clock771MHz
More VRAM (8GB vs 2GB)
Larger VRAM bandwidth (115.2GB/s vs 40.10GB/s)
1152 additional rendering cores
NVIDIA Quadro M520 Mobile 's Advantages
Released 3 years and 6 months late
Lower TDP (25W vs 100W)