NVIDIA Quadro P1000 's Advantages
More VRAM (4GB vs 2GB)
Larger VRAM bandwidth (80.19GB/s vs 48.06GB/s)
256 additional rendering cores
NVIDIA Quadro P520 Mobile 's Advantages
Released 2 years and 3 months late
Boost Clock has increased by 1% (1493MHz vs 1480MHz)
Lower TDP (18W vs 47W)