NVIDIA Quadro K6000 SDI 's Advantages
More VRAM (12GB vs 2GB)
Larger VRAM bandwidth (288.4GB/s vs 32.06GB/s)
2624 additional rendering cores
NVIDIA Quadro P400 's Advantages
Released 3 years and 7 months late
Boost Clock1252MHz
Lower TDP (30W vs 239W)