Wii U GPU scanned and analyzed
[URL="http://www.chipworks.com/blog/technologyblog/files/2013/02/C10234F5_Poly_b.jpg"]Full-size photo here[/URL] ([i]very[/i] big)
[URL="http://www.chipworks.com/blog/technologyblog/2013/02/04/looking-at-the-wii-u-graphics-processor/"]Chipworks write-up here.[/URL]
[B]What am I looking at?[/b]
Well, the first thing to note is that we're looking at something very different from a standard R700 die (we know that Latte is based on AMD's R700 line originally). This makes it more difficult than we'd hoped to analyse, as comparison to existing AMD die shots would generally be our main strategy. There are a few things we can say so far, though:
- The die is exactly 11.88 x 12.33mm
- The large orange block on the left is the 32MB of eDRAM (MEM1).
- The smaller orange block above it seems to be about 3MB of eDRAM. This might be the framebuffer for Wii mode, or the L2 texture cache, or something else, we're not 100% sure at this point.
- In the lower left there is what appears to be a dual-core ARM (used for security/streaming purposes) and possibly a DSP (or custom logic for the video streaming).
- Along the bottom and right sides of the chip are likely DDR3 controllers. The top and left sides of the chip are probably for communication with the CPU.
- All the small dark orange/black blocks you see over the GPU part of the die are SRAM blocks. The number and formation of them should give us clues as to what part of the chip does what.
- The eight squarish groupings on the right hand side are possibly the VLIW5 shader clusters. However, due to the apparent increased amount of SRAM there, along with the unusual layout and the general changes to the die, it's entirely possible that the number of shaders in each cluster has changed from R700 dies. In fact, at this point it's even possible that the microarchitecture itself has changed, a la the VLIW4 used in some of AMD's 6000 series GPUs. Therefore, we could have a fairly unusual number of shader cores.
- It's likely there's some legacy Broadway hardware on there for BC purposes.
Thanks to -
Geeze, we're looking at about 178 gflops based on the shader count and the known clock speed. Gflops aren't everything and I'm sure it's still better than the old PS3/360 GPUs, but compared to the rest of the eight generation? It will be like the Wii again.