German site ATI-Forum probably scored a coup of 2009 – according to their sources, ATI’s RV870-based cards are already out at selected partners.
We cannot say was this leak was a reaction on our joint-exclusive story about nVidia’s GT300 architecture, but one thing is for sure – ATI wants to bring out their Cypress board as soon as possible – planned for July 2009.
The alleged specifications of ATI Evergreen reveal that this chip is not exactly a new architecture, but rather a DirectX 11-specification tweak of the RV770 GPU architecture. Just like nVidia’s GT300 architecture, the actual Evergreen chip is manufactured in TSMC’s 40nm half-node process, packing more transistors than GT200 chips. Regardless of what ATI says about nVidia and large dies, the fact of the matter is that ATI is making a large die as well – but the company will continue to use the dual-GPU approach to reach high-end performance.
The Evergreen chip should feature 1200 cores, divided into 12 SIMD groups with 100 cores each [20 "5D" units], while RV770 was based on 10 SIMD group with 80 cores total [16 "5D" groups consisting out of one "fat" and four simpler ones]. Thus, it is logical to conclude that when it comes to execution cores, not much happened architecturally – ATI’s engineers increased the number of registers and other demanding architectural tasks in order to comply with Shader Model 5.0 and DirectX 11 Compute Shaders. The core is surrounded with 48 texture memory units, meaning ATI is continuing to increase the ROP:Core:TMU. For the first time, ATI is shipping a part with 32 ROP [Rasterizing OPeration] units, meaning the chip is able to output 32 pixels in a single clock.
When it comes to products, ATI plans to launch four parts: Radeon HD 5850 and 5850X2 in more affordable pricing bracket and HD5870 and HD5870X2 for the high-end parts. While there were no clocks for the Radeon HD 5850/5850X2 parts, alleged clocks for HD5870 and HD5870X2 reveal that for the first time, an X2 part is clocked higher than a single-GPU part. Was this a requirement of SidePort memory interface, we are not aware atm. German site Hardware-Infos placed all of the data in a very convenient table, which we are running here with permission. Their story also contains more data about the upcoming ATI RV870 architecture.
ATI 4870 vs 5870 table…courtesy of Hardware-Infos
These units should result in 2.16 TFLOPS for the HD5870 and 4.56 TFLOPS for the dual-GPU part. Yes, you’ve read correctly – we are going from 1TFLOPS chip to 4.6TFLOPS within 13 months. Is it now clear that CPUs are in a standstill when it comes to performance improvements? The biggest question though is – while there is no doubt that ATI pulled another miracle out of their hat with a brilliant on-time execution, releasing a 40nm part that will be relatively cheap to manufacture. BUT – can it beat nVidia’s GT300 and by how much?
Some journalists allegedly have miracle 8-balls and claim that the ATI cards will blow nVidia out of the water. We are not so certain… stay tuned.