Comparison of Sapphire Nitro+ Radeon RX Vega 56 video card vs ZOTAC GeForce GTX 1080 Ti AMP Edition video card by specifications and benchmarks. Sapphire Nitro+ Radeon RX Vega 56 runs at 1.266 GHz+ 10 % base clock speed and has 8 GB of HBM2 memory, while video card ZOTAC GeForce GTX 1080 Ti AMP Edition runs at 1.569 GHz+ 6 % base clock speed and has 11 GB of GDDR5X memory. The TDP of the first video card is 325 W+ 55 %, and the second is 270 W+ 8 %. Compare the table of benchmark results to find out which graphic card is better.