PCIe 4.0 X 16 vs 3.0 X 16

[Braegnok]

I'm building a new folding rig this weekend, going with Asus X570 WS. And using an open air VEDDHA 6-card mining chassis with cards up above the motherboard.  

Using (30cm) Linkup Extreme 4.0 X 16 riser cables. 

Will be running two 2080TI FE cards,.. stacking the FE cards in PCIe slots generates too much heat for top card inside typical chassis. 

I'm not even sure if the riser cables will run Folding @ Home stable yet,..

or if PPD might be effected running 4.0 vs 3.0 X 16.  

 

Edited October 4, 2019 by Braegnok

[ir_cow]

Well considering the RTX 2080 Ti barely uses 8X PCIE 3.0, you won't see any benefit. Second, I thought PCIE 4.0 distance limit is 10cm from the CPU. but IDK since i've seen a few boards supporting 4.0 on the lowest slot which is clearly further away than that. I was able to get nearly the same PPD with PCIE 4x 2.0 as 8x 2.0 with 1080 Ti cards. I think it was like 20-30K less? It's been awhile since I setup a dedicated folding rig.

Fold@home does run off 1x USB 3.0 riser lol. Just not that well.

[Braegnok]

I was worried about the distance limit with 4.0 set-up, and the fact current PCIe  4.0 specification does not include MB + riser cable + GPU. May cause errors, as some overclocked GPUs had reported problems due to limited tolerance. 

Kinda leaning towards going with my old Intel board with PLX Chip 3.0 X 16 set-up first, and see what happens. If everything works then just call it good. 

[ir_cow]

Yeah no need to spend unnecessary money. Try 16x PCIE 3.0 and compare to 8x PPD. Its a hassle, but it will give a better understanding of how little Folding@home bandwidth actually uses compared to gaming.

Things do change and the FoldingCore is always updating. What are they on now Core22? Maybe it uses more bandwidth than before.. IDK.

[Braegnok]

+1, thanks for the advice. 

Only a few mods left to complete on chassis and I'll be up and running,.. mounting riser cables up top, drill & tap new stand-offs, fans,.. 

 

 

Edited September 27, 2020 by Braegnok

[Braegnok]

Update : The 3.0 x 16 Linkup Riser Cables work as advertised.  https://linkup.one/linkup-pcie-3-0-16x-64gb-s-shielded-twin-axial-pci-express-riser-cable-port-extension-card-universal-90-degree-socket-20-cm/

I confirmed  3.0 x 16 on both cards running NVLINK Bridge with riser cables and without, running 3DMARK Time Spy Extreme, Fire Strike DX11 3840x2160.

Also running NVLINK Bridge, playing Rise of the Tomb Raider (DX12) vary high preset, all GFX features enabled @ 3840x2160 - Geothermal Valley (FXAA) averaging 131.76 FPS both with the riser cables and without.

The riser cables have no effect on running Folding @ Home. I received same PPD, had same TPF for all Work Units, with riser cables and without.

Imgur Link  :  https://imgur.com/a/ytPGf7b

 

 

 

 

Edited October 11, 2019 by Braegnok

[ir_cow]

This is a little late but the card has to support PCIe 4.0 for it to run at that speed. Only the RX 5700 is PCIe 4.0 right now. Not that it actually makes a difference (yet).

Anyways 5 Mill PPD is awesome! To bad folding coin is dead. Would have been nice a 2 years ago

[Braegnok]

Not much difference gaming FPS running x8 PCIe 3.0 vs x16 PCIe 3.0, and I guess that's because few games ever saturate the 3.0 slot, so most likely running your GPU at PCIe 4.0 doesn't actually translate into more practical gaming performance today.

I think where PCIe 4.0 matters more is storage, with M.2 PCIe 4.0 SSD hitting 5GBps reads and 4.3GBps write speeds.