NVIDIA GeForce GTX 780 Rev. 2 's Advantages
Larger VRAM bandwidth (288.4GB/s vs 192.1GB/s)
896 additional rendering cores
NVIDIA GeForce GTX 1660 's Advantages
Released 5 years and 6 months late
Boost Clock has increased by 98% (1785MHz vs 902MHz)
More VRAM (6GB vs 3GB)
Lower TDP (120W vs 250W)