Some 3 months from now, the new-generation Dual Socket 2011 Xeon platform will be out now. What to do with the 80 PCIe 3.0 lanes on it?
Sometime in March, after the widely known delays, the Dual Socket 2011 processors and boards – the Xeon E5 'Romley' platform – should finally be out. One interesting new feature is, of course, 80 PCIe 3.0 lanes in total on each of those boards, as each chip has 40 of them. That is, of course, in addition to PCIe 2.0 lanes going to the I/O chips.
Now, you could obviously have four full x16 v3 PCIe slots there for quad graphics card setups, as well as an extra pair of x8 slots for, say, superfast SSD enterprise card and an interconnect board, but will any boards actually implement that, and what can be supported on them if you want to set up a parallel graphics rig?
The EVGA SR-X mainboard is the only one known up to now to have the support for both SLI and CrossFire among the Dual Socket 2011 offerings expected at launch, including of course quad-GPU modes of both parallel graphics combinations. Other boards expected, such as Intel 'Crown Pass' , have even more slots than the SR-X, but, as of now, are only expected to support CrossFire from AMD – including the quad mode – at launch. Intel's mobo is, in a way, more flexible slot-wise than the EVGA one as you can put in four full double-width GPUs at their own x16 slots, and still have one more PCIe slot available for other things such as DSP sound or SSD or whatever. And, it has full 16 DIMM slots for DDR3-1600+ memory. Either way, both boards are gigantic size wise, Intel is also there this time with the 14 x 15 inch format.
Worried about GPUs that are on PCIe lanes from different CPUs communicating slowly? Well, don't worry so much. Remember there are TWO QPI links between those Xeon E5's? Each running at 8 GT/s, the same raw lane speed as PCIe v3, for better sync? The 64 GB/s interprocessor bandwidth provided by these two links should support a fair bit of inter-GPU communication in this case, in parallel with the inter-core comms from both CPUs.
Anyway, can't wait to see the new stuff – especially if Intel does come out with the unlocked SKUs of these Xeon E5's at launch…