The AMD Radeon RX 500 series was released this week and the new Polaris based graphics card series consists of the Radeon RX 580, RX 570, RX 560 and RX 550. These cards are mostly all based on the Polaris architecture found on the RX 400 series as they use the same cores. AMD tinkered under the hood of the Polaris GPU a bit and took advantage of improvements in the manufacturing process to get higher clock speeds than they could get last year when the RX 400 series was launched. AMD didn't send over any reference models this time around, so we were given the Sapphire NITRO+ Radeon RX 580 Limited Edition graphics card. This is a factory overclocked model and just happens to be the fastest Radeon RX 580 that you can buy today from Sapphire.