NVIDIA Tesla K80 's Advantages
More VRAM (12GB vs 4GB)
Larger VRAM bandwidth (240.6GB/s vs 96.13GB/s)
1984 additional rendering cores
NVIDIA Quadro P620 Mobile 's Advantages
Released 3 years and 3 months late
Boost Clock has increased by 75% (1443MHz vs 824MHz)
Lower TDP (40W vs 300W)