Typical GDDR5 data rates on shipping products are mid-way between PCIE 1 (2.5 Gbps per pin) and PCIE 2 (5.0 Gbps per pin), but in all cases you need an extremely wide bus to get the kind of bandwidth a modern GPU requires. An x16 or x32 bus isn't going to do the job.
The point I'm trying to make about OpenCL vs OpenGL is that if you structure the OpenCL app (or any compute app) properly you don't have to access data in the other GPU's memory very much in the first place.
yes it make sense but now is not all the efficient it should be cuz well even if that fix the hardware ooops with the link between GPUs the developer have to be extremely careful controling the code to avoid intergpu processing with really massive loops operations or it will suffer an slowdown or crash (and that explains why cuda apps mostly arent multigpu aware or are only for really expensive software). i think a more CPU aproach should be more efficient here for both opengl and opencl aka each gpu been electronicaly aware of the other and the ability to map memory for common use
Originally Posted by bridgman