NVIDIA GeForce GT 640 's Advantages
Lower TDP (65W vs 250W)
NVIDIA GeForce GTX 780 Ti 's Advantages
Released 1 years and 5 months late
Boost Clock928MHz
More VRAM (3GB vs 2GB)
Larger VRAM bandwidth (336.6GB/s vs 28.51GB/s)
2496 additional rendering cores