boristsybin wrote:QuintLeo wrote:AMD FX series are a lot lower cost for the same number of cores,
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Ignore "hyperthreaded" cores - they do NOT work well to support folding GPUs, they MIGHT be worth a QUARTER of a real core.
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In fact, ignore AMD
AMD FX supports only pci-e v2, that, in theory, may limit gpu productivity
i3 4130 with HT enabled is enough for three 1080ti, so HT does work well to support folding GPUs
amd gpus loads CPU less than nVidia`s :
with amd gpu, FahCore uses 100% per thread on task start and and drops to ~60% per thread on main time of task count,
with nVidia, FahCore uses 100% of CPU thread whole folding time.
PCI 2.0 16x is more than enough for any GPU - even the 1080ti.
8x can lose a little bit, but commonly only a few percent at most even on the 1080ti.
Any quad core should be ENOUGH to support 4 x 1080ti - but have you priced Intel quad-cores vs the FX 6300 6-core or even the 8320e 8-core lately - and given my results as I talk about below, I'm not sure a single core is enough to support a 1080ti fully even WITH Hyperthreading enabled unless it's a very HIGH end CPU.
I tried to run *2* 1080 ti with a G4600 (Kaby Lake 2 core WITH hyperthreading, the SAME as a low-to-midrange Kaby Lake i3 except less cache) - the setup was DID CPU LIMIT on some work units, and was right on the edge most of the time on the rest.
Dedicated folding machine that wasn't running anything else, one 1080ti on a PCI-E 3.0 16x slot the other on a PCI-E 3.0 4x slot.
I can't recommend trying to run a 1080 ti on a SINGLE core - even with hyperthreading - as it gets very marginal.
AMD GPUs load the CPU a lot less in general because they're doing less work - FAH is not AMD GPU friendly, something about the differences between AMD and Nvidia GPU design make FAH work a LOT better on Nvidia GPUs.