Like its 2016 predecessor, the rebranded Radeon 600 series GPUs are based on the same 14nm Polaris GPU architecture, as well as AMD’s already archaic Graphics Core Next (GCN) microarchitecture. Moreover, the specifications of each graphics card are virtually identical to their 500 series counterparts, including the amount of graphics memory and their respective clockspeeds. In terms of models, the Radeon 600 series comprises the Radeon RX 640, Radeon 630, Radeon 625, Radeon 620, and the Radeon 610. To be clear, both the Radeon RX 640 and Radeon 630 are based on AMD’s Polaris GPU, while the Radeon 625 and 620 are based on the older Topaz GPU architecture and Orland for the Radeon 610.
It’s not wrong to say that AMD has a habit of refreshing older GPU architectures. The company has been doing it since the release of its Radeon R9 200 series, which is based on a 28nm die lithography. For the record, AMD isn’t planning on releasing its Radeon 600 series as standalone products. At this point, it’s possible that the company only refreshed its older GPU series at the behest of OEMs who wish to sell their desktop and notebook solutions with “newer” generation hardware. (Source: Techspot)