Just a paper for now, so it is surely far off. Clearly AMD and Intel will beat them to products using multi die solutions but it's still pretty interesting to read.
http://research.nvidia.com/sites/de...U:-Multi-Chip-Module-GPUs//p320-Arunkumar.pdf
http://research.nvidia.com/sites/de...U:-Multi-Chip-Module-GPUs//p320-Arunkumar.pdf