How likely will there be a motherboard that supports 256GB RAM and 64x2 PCIe 3.0 lanes (i.e. x16x16x16x16) in the near future?
In the server world, maybe. In the consumer world, approx equal to the number of "R's" in 'fat chance'.
Reply to USAFRet
Thanks. How is the Epyc CPU compared with the Threadripper? It seems that they have lower clock speed at around 2GHz.
Reply to modeonoff
That is typical of workstation and server chips. The goal is more cores at the same power consumption for multithreaded workloads, not necessarily per core performance. They'll have their boost clocks, but essentially they are guaranteeing every core, max load, to run at that speed within the TDP.
If you want the best of both worlds, Intel makes plenty of high clock frequency Xeons with 8 cores. E5-1680 v4 3.4 up to 4.0, and I know from experience they'll often boost over that for single threads. They have some pretty high core count 24 core or so chips that boost to 3.4, but they'll have that same 2ish Ghz base clock.
Though at this point the i9-7980XE would be the best mix between core count and core frequency (Though they might need to make some fancy motherboards and power supplies with thicker gauge wire, some of the reviewers were pulling nearly 500W through the socket, but getting it around 4.5Ghz)
Reply to Eximo
Just checked the price: E5-1680 v4 alone costs about 2K. That would be a bit expensive given that I will add 1-2 1080Ti initially. Usually I prefer to buy brand new.
I considered the Xeon W-2125 and W-2135. The specs seem good but I cannot find them in Amazon, newegg or other local computer stores. Where can I get these CPUs brand new? I don't use eBay.
Reply to modeonoff
They may not be commercially available except by buying an entire system from an OEM.
Sounds like you should be looking at a lesser i9 then, perhaps the i9-7920X?. That will get you 44 PCIe lanes and 12 cores.
Still ludicrous, you don't really need x16 to run a pair of 1080Ti, 8x/8x is enough. And since SLI support is limited to two cards, and multi-gpu isn't really a thing that should be quite good.