Comparison of XFX Radeon RX 590 Fatboy 8GB video card vs PowerColor Hellhound Radeon RX 6600 video card by specifications and benchmarks. XFX Radeon RX 590 Fatboy 8GB runs at 1.469 GHz base clock speed and has 8 GB of GDDR5 memory, while video card PowerColor Hellhound Radeon RX 6600 runs at 1.626 GHz base clock speed and has 8 GB of GDDR6 memory. The TDP of the first video card is 225 W, and the second is 132 W. Compare the table of benchmark results to find out which graphic card is better.