Comparison of PowerColor Red Devil Radeon RX 7900 XTX Limited Edition video card vs XFX Speedster MERC 310 Radeon RX 7900 XTX Black Edition video card by specs and benchmarks. PowerColor Red Devil Radeon RX 7900 XTX Limited Edition runs at 1.900 GHz base clock speed and has 24 GB of GDDR6 memory, while video card XFX Speedster MERC 310 Radeon RX 7900 XTX Black Edition runs at 1.900 GHz base clock speed and has 24 GB of GDDR6 memory. The weight is different, -- vs --. The TDP of the first video card is 355 W, and the second is 355 W . Compare the benchmark results to find out which video card is better.