GPU Passthrough Recommened CPU

Threadripper would probably be excellent when its fixed, 60 pcie lanes - nvme not stuck on the dmi etc

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Yeah, if it is “going to be” fixed in under a year I feel like I’d get more use out of it in the long-term. It is a similar price here for the TR 1950x and the i9 7900x. So, 16 cores, vs 10. I feel like 10 is probably enough but 6 extra seems…cool. Lol!

Okay, so used equipment is not possible. In that case, I’d wait for Threadripper to be sorted. The PCI-E errors has to be related to the microcode so wait for the AGESA update that fixes Threadripper.

Thought I’d post a brief recap to where I am with things, sort of a TL;DR version -

I started off building a 1950X / Gigabyte X399 Aorus 7 system - it let me validate some aspects of TR, enough so that it gave me some confidence to go ‘all out’ on building a second box, with the Asus Zenith Extreme.

My goal was to have the Zenith box as a desktop and use the “other” 1950X system as my virtualisation server - however, I started to run into some issues - mainly painpoints by not being on Intel. Given that ECC wasn’t a major concern, I’ve since returned the 1950X CPU back to Amazon for a full refund of $879.99 - especially when Amazon is NOW reselling the same CPU for 799.99 (haha!).

During the same time, I ended up ordering a second Zenith Extreme board, which Amazon will let me hang onto till 1st Feb 2018; so if I want to return it, I’ll have to do it then… BUT instead, I’ve decided to keep the mobo towards TR once all these issues are sorted or Threadripper 2. Who knows, I may be able to snag a 1950X for $750 in January? That wouldn’t be too bad.

TL;DR I now have an i9-7920X on the way for $1,099/- (Amazon) and a Strix X299 mobo. Will pickup a Vega 64 and have a play with GPU pass through then :wink:

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For ease of use, Intel is the way to go. AMD requires a bit more work and the patches for native performance are not currently available. I’m just going off Wendell’s recommendation that Intel is the best “plug and play” solution, but AMD will require a bit of work.

I wholeheartedly support AMD and would love for people to use it. I’m actually currently building an R7 system for this purpose exactly. I’m just not really happy with the software support for AMD at the moment. That said, it should change with 4.16 release.

On a side note: Whoever at AMD decided to pre-empt Intel on their naming scheme should be fired. It was a good meme, but aside from that, it’s completely unprofessional and annoying.

Ryzen 7 is mature now, I’d say that TR is going to take a bit longer to mature because of the smaller user base.

@bsodmike has a lot of experience in the field. If you’ve got questions about TR, he’s your guy.

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Ty for that insight @bsodmike. So threadripper isn’t quite there for this scenario, whereas x299 is dead easy. I will definitely keep that in mind. Thank you!

Okay, so if you @SgtAwesomesauce are making an R7 build, that would suggest to me that 8 cores and 16 threads is plenty for gpu passthrough without any bottlenecks to the windows vm. Would that be correct? Because that would lower the barrier to entry quite significantly and let me buy more cooling/storage/ram.

Remember, for me the only thing windows vm will do is play games like PUBG, WoW, GW2, CS:Go, etc. The linux host is where I will be doing my video editing etc.

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It really depends on your use case. If games will be your most resource intensive operation, 8/16 is plenty for almost all games.

@SgtAwesomesauce, yes. Games are the ONLY thing the windows vm will do. All video editing, photo editing, rendering, etc will be done under linux.

In that case, you’ll be very happy with an R7 build.

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Thank you very much. you just saved me 1.5k dollars :wink:

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Can you send some of that my way? “finders fee” :smiley:

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sorry, your message is breaking up…((##&[email protected]&[email protected]#()(@(…can’t…hear…you…

dial tone ends

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typical… LOL.

If you know, were your issues with nVidia something that’s been fixed with patches, or is it still the case that GPU passthrough requires Vega? And is this limited to threadripper? I’m curious as I was thinking about building a 1950X with KVM passing through an nVidia 1070/1080.

I’d like to direct you to this thread. There’s a lot of TR passthrough discussion here. I’m fairly certain it will be fixed soon, since it appears to be an issue that should be able to be fixed via UEFI.

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As far as I know the issues are still there.
It’s same issue reported by @bsodmike and by others on the VFIO reddit / AMD Support forums.
It’s basically that PCIe devices got stuck in “off/powersave mode” (D3 powerstate crap). Could not pass through NV graphics cards, USB card or a Soundblaster Z.

RMA’d the system for X299 parts (which sucked, because $$). X299 is running pretty good with VFIO for me (OpenSUSE Tumbleweed and Fedora 27), except for some snags with hugepages :persevere:

Edit: the TR system wouldn’t even boot (no post) with Fresco Logic chipset USB PCIe cards.
Edit2: post above is awesome, @SgtAwesomesauce delivers again!

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Ugh… Thanks! So, if I’m understanding correctly: threadripper – which should be the obvious choice for virtualization with its PCIe lanes – is currently “unusable” for that task?

What about the i9s (especially with nVidia’s 1070/1080 passthrough)? Don’t really want to pay more (for less…) and am willing to patch kernels, etc., but ultimately need something that, well, actually works.

The SMT for Zen only affects people who do cpu pinning and try to pass SMT to guest.
Qemu will not provide correct SMT information to identify core to cpu topology.
Guest will schedule 2 heavy threads on 1 physical core, even if there are unused ones, and host will not be able to schedule them to different cores due to pinning.

Thanks darling, I’m just your humble information broker.

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i9 works. I pass through a 1080ti, soundcard, nic and a usb card. I use an RX460 for the host, amd gpus in linux are great!
On the flipside, Nvidia are douchebags. Just follow the archwikiguidethingy for how to work around error code 43.

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