The internal documents indicate Larrabee will have between 4 and 24 IA cores and Valich says this should give Larrabee over 1 Tflop on the high-end. To put this in perspective, rumour has it that NVIDIA's upcoming GT200 GPU delivers around 1 Tflop.
Intel has not provided information about how many IA cores Larrabee will actually include, other than saying that it will have “lots of cores”. According to our information “lots” will really be a matter of perception, as internal documents seen by us currently indicate between four and 24 IA cores. On the high-end, this should be well enough to put the performance of Larrabee above into 1 TFlop mark. A big mystery remains a huge pink placeholder block in Larrabee drawings that is simply described as “cache” at this time.
We expect GDDR5 memory and the 1024-bit bus as key factors for Intel to achieve hundreds of gigabytes of bandwidth. The internal path is targeting 1 TB/s. We have seen a similar concept with ATI's failed R600 design (1024-bit internal, 512-bit external) and Intel expects a lot from GDDR5, most notably to keep the tracing lengths as short as possible.