Comparison of PowerColor Radeon RX Vega 56 Nano Edition video card vs ASRock Radeon RX 6500 XT Challenger ITX 4GB video card by specifications and benchmarks. PowerColor Radeon RX Vega 56 Nano Edition runs at 1.156 GHz base clock speed and has 8 GB of HBM2 memory, while video card ASRock Radeon RX 6500 XT Challenger ITX 4GB runs at 2.200 GHz base clock speed and has 4 GB of GDDR6 memory. The TDP of the first video card is 210 W, and the second is 107 W. Compare the table of benchmark results to find out which graphic card is better.