A Redditor by the name of Alchemist1123 has found that AMD has updated their mobile graphics page to include information on the r9 400M series, AMD’s upcoming lineup of Mobile GPUs based on Polaris architecture.
The R9M485X seems to be based on Polaris 10 architecture, based on rumours, whereas the R9 M470x and R9 M470 seem to be based on Polaris 11. 32 compute units puts the R9 485x at 2048 cores, which puts it very close to the rumored 2304 cores that Polaris 10 may contain-this is likely a cut down version for mobile.
The R9 m470x willhave 896 shader cores, and the R9 470 will have 768. With AMD’s R9 M485X offering up to 8 GB of GDDR5 VRAM, and the R9 M470X offering up to 4 GB of GDDR5, the new GPUs should stay caught up with VRAM requirements of modern games for a while.
Keep in mind the number of cores are not necessarily the only indicator of performance. We aren’t sure of what the maximum core clock speeds will be(only the memory clocks are listed), and we aren’t sure of how much of an improvement architecture improvements to the cores themselves will bring.
Update/edit: Reddit user an_angry_moose speculates that the new M400 series GPUs could be a rebrands of the R9 M300 series. The reasoning is that the specifications listed for the 3 new devices are identical to some of the devices listed under the r9 M300 series. User /u/vince789 counters by citing a rumor by TechPowerUp, indicating that the specifications of the new GPUs also match the specifications provided by Industry sources regarding Polaris 10 and Polaris 11.
Personally, I find the possibility of rebrands unlikely. AMD’s Polaris GPUs are designed in a way that allows them to excel in the Laptop market. While they are not high end or intended for the enthusiast market, they provide substantially better power efficiency than their previous generation of GPUs. Better power efficiency in laptops means improved battery life and potential for slimmer/lighter design(don’t need as large of a heatsink).
Improved power efficiency in a desktop simply means drawing less power from the wall, and not needing a high wattage power supply. Desktop PC gamers often don’t care about power efficiency, and mainly prefer better performance. Those seeking the best performance for their money with a smaller budget will likely find that purchasing a used GPU will provide better performance than purchasing a new Polaris 11-based GPU for a similar price, with the only downside being the dramatically increased power consumption.
Used AMD Radeon 7950s are currently selling for as little as $100, and their market value is expected to drop significantly when new products come out, and people begin to sell their old GPUs after upgrading.
Basically, it seems unlikely to me that AMD would utilize rebrands on the one market that benefits the most from their cutting-edge technology. We’ll have to wait and see to know for sure.
The page can be found here: http://www.amd.com/en-gb/products/graphics/notebook/r9-m200