AMD R600 technology, yet again
- T'n'T - 1
Author: Hrvoje Jakovac
Date: 04 May 2007
Around 700 million transistors providing up to 320 superscalar stream processors, programmable Tessellation Unit, AVIVO, UVD, CrossFire support, these are the main things we'll cover for the Terms 'n' Technology start. These chips' roots are clearly in the Xenos design (XBOX 360), but with new dispatch processor and, of course, superscalar ALU's - dedicated branch execution units and texture address processors. Shaders are actually 5-Way, helping R600 to deliver close to 500 GigaFLOPs per GPU (475), or close to a TeraFLOP in CrossFire (950 GigaFLOPs). This makes the chip incredibly powerful, having more then 1 GigaFLOP/mm2. Texture units are also improved, being able to do 64-bit HDR textures at full speed and 128-bit FP textures at half speed.
Having fully distributed memory bus (512-bit) with more then 100GB/s per second bandwidth and eight 64-bit memory channels is pretty impressive. Vertex cache is also 8x larger then on X1950, which is a significant improvement, and all of the shaders are capable of doing geometry and vertex processing, and AMD claims that power-wise, they are able to pull out up to 10x more vertex power compared to X1950 and up to 50x more geometry power compared to what AMD calls "fastest competing DirectX 10 GPU's". Go figure that one out. We're really eager to see all of this in action later on today and in the next couple of days, tortured by high AA and AF settings and high resolutions. Theoretically, this should provide more gentle performance-drop curve, definately better then on previous chip generation.
Xenos heritage also means that the ATI Radeon HD 2000 series GPU's have a new programmable Tesselation Unit, which we "touched" in our previous articles (make sure to check them out here
Benefits of this fully programmable unit should be pretty huge, especially when dealing with geomtery data, which should in real life mean more details, more realism, and overall better picture quality. We've been blindly staring at the picture quality for weeks now, and it's pretty incredible. For example, when rendering people's faces, tesselation unit can do a lot of stuff - manage displace mapping, manipulate morph targets, deformation, animation data etc. AMD hopes to change the difference between the cinema-type rendering and in-game type rendering to close-to-equal-quality status. Combined with huge bandwidth these chips have, we're yet to see some interesting things happening. More flexible AA features should also help, while the max resolution is set to 2560x2048. Of course, physics is supported, as well. Also, our "favorite" thing about high-end Radeons of the previous generations, the master card - is gone. Instead, you have two internal very much SLI-alike CrossFire
connectors. In not so-distant future, you'll be able to do a lot of cool and interesting things with digital or webcams, and for example pictures on your hard drives, but let's leave it at that. We had a nice chat about that quite awhile ago with one of AMD's officals. AMD promises very good CrossFire scaling, which we will check very soon.