The Radeon R9 285 will be price in the $300 US range which means that Tahiti based cards will be receiving a major price cut as hinted previously to make room for the new cards otherwise having both Tahiti XT and Tonga at the same price will mean poor sales for the inferior product of the two. The card will launch in Q3 2014 and the exact date is pitted somewhere between late August and Early September but it is definitely coming out soon and we will start receiving more information in the coming weeks.
The specifications for the card include a 2 GB GDDR5 buffer running across a 256-bit bus interface. This is actually lower than Tahiti’s 3 GB GDDR5 VRAM and 384-bit bus but Tonga is rumored to include faster 7 GHz memory modules which will result in higher bandiwdth and card makers will have the option to launch 4 GB models later in production.
The card will be built on a new architecture which is presumably the GCN 2.0 design and not the GCN 1.1 architecture which has been featured on Bonaire and Hawaii. The Tonga graphics architecture will be built on the 28nm node from TSMC (if rumors are to be believed) and would feature a new design scheme introducing latest architectural improvements such as new ACE (Asynchronous Compute Engine) Units and more focus towards compute shaders. It is also mentioned that Tonga will retain the basic technologies of the Radeon lineup such as
Mantle, TrueAudio and XDMA for CrossFire support. Performance efficiency would be a main focus of the new card and the ratings could be expected somewhat similar to Maxwell if not the same.
Read more:
http://wccftech.com/amd-tonga-based...256-bit-memory-replaces-tahiti/#ixzz393TXSQVz