Comparison of ZOTAC GeForce GTX 1080 AMP Extreme video card vs KFA2 GeForce GTX 1660 EX (1-Click OC) video card by specifications and benchmarks. ZOTAC GeForce GTX 1080 AMP Extreme runs at 1.771 GHz+ 10 % base clock speed and has 8 GB of GDDR5X memory, while video card KFA2 GeForce GTX 1660 EX (1-Click OC) runs at 1.530 GHz base clock speed and has 6 GB of GDDR5 memory. The TDP of the first video card is 270 W+ 50 %, and the second is 120 W. Compare the table of benchmark results to find out which graphic card is better.