All of which brings us closer to some additional guessing about likely clock speeds. Today's GPUs range from around 700 to 1500MHz, if you count GT200/b shader clocks. G92 shader clocks range up to nearly 1.9GHz. But Larrabee is expected to be produced on Intel's 45nm fab process, which offers higher switching speeds than the usual 55/65nm TSMC process used by Nvidia and AMD. Penryn and Nehalem chips have made it to ~3.4GHz on Intel's 45nm tech. At the other end of the spectrum, the low-power Atom tends to run comfortably at 1.6GHz. I'd expect Larrabee to fall somewhere in between.


In the numbers above, I'm betting that GDDR5 memory will make it up to 1GHz by the time this GPU is released, and I'm counting on Intel's texture filtering logic to work at half the rate on FP16 texture formats. We can't determine the pixel fill rate because Larrabee will use its x86 cores to do rasterization in software rather than dedicated hardware. I'm just working my way through Michael Abrash's write-up of the default Larrabee rasterizer now, but I don't think we can assume a certain rate per clock given how it all works.

http://techreport.com/discussions.x/16920