I'm a grad student looking to purchase a many-GPU system for our research lap. I'd like to maximize both CPU core and GPU count. The best I can find that maximizes both of these is a Tyan Intel-based system (http://www.tyan.com/product_SKU_spec.aspx?ProductType=BB&pid=412&SKU=600000188), which supports 12 CPU cores and 8 double-wide GPUs. Is there any sort of equivalent (or better) in the AMD world? The best I can find is a SuperMicro system that can sport 4 double-wide GPUs. I've read that a company called Aprius had planned to produce an 8-way GPU system, but it looks like the product may have been cancelled.
I would much prefer an Opteron-based system. I believe it's memory/cache hierarchy may provide more deterministic program execution (something that is important in our research).
Any recommendations? Please tell me these systems exist!