Comparison of AMD Radeon RX 550 (Lexa) video card vs ASRock Phantom Gaming Radeon RX 550 4G video card by specifications and benchmarks. AMD Radeon RX 550 (Lexa) runs at 1.100 GHz base clock speed and has 2 GB of GDDR5 memory, while video card ASRock Phantom Gaming Radeon RX 550 4G runs at 1.100 GHz base clock speed and has 4 GB of GDDR5 memory. The TDP of the first video card is 50 W, and the second is 50 W. Compare the table of benchmark results to find out which graphic card is better.