My wife and I are discussing getting new gaming rigs and I mentioned using Unraid + GPU Passthrough. 

 

Is it practical to have 1 machine with multiple gaming VMs? Our monitors are all within a few feet of each other, basically a big lan party.

 

Planned Specs:

1. AMD RYZEN 9 3900X 12-Core 3.8 GHz 

2. 64 GB Ram

3. Motherboard with 3-4 PCI-E GPU Support (if it exists)

4. Nvidia 1660 ti x3 or 4

 

I would give each gaming rig 1 dedicated GPU, and 16GB of ram + a 512GB ssd drive.

All 3 VM's would get 4 cores, unless we go with 4, then I would possibly look at the 16 core. 

 

A positive to this approach is that the system is contained within a box with an exhaust fan sucking the air out keeping the room cool.

Edited December 18, 20196 yr by Awesomeb

5 hours ago, Awesomeb said:

My wife and I are discussing getting new gaming rigs and I mentioned using Unraid + GPU Passthrough. 

 

Is it practical to have 1 machine with multiple gaming VMs? Our monitors are all within a few feet of each other, basically a big lan party.

 

Planned Specs:

1. AMD RYZEN 9 3900X 12-Core 3.8 GHz 

2. 64 GB Ram

3. Motherboard with 3-4 PCI-E GPU Support (if it exists)

4. Nvidia 1660 ti x3 or 4

 

I would give each gaming rig 1 dedicated GPU, and 16GB of ram + a 512GB ssd drive.

All 3 VM's would get 4 cores, unless we go with 4, then I would possibly look at the 16 core. 

 

A positive to this approach is that the system is contained within a box with an exhaust fan sucking the air out keeping the room cool.

 

2-games-1-PC is relatively easy to do with Ryzen.

 

You might want to make your life easier with Threadripper for a 3-gamers-1-PC build.

X570 motherboards have at most 3 PCIe x16 slots and the bottom most one will cover up the internal IO (you just need to have a look at a X570 motherboard picture to understand what I mean).

So assuming you can pass through all 3 (the bottom one will certainly need ACS Override), case choice and PC building finesse will be important.

 

4-gamers-1-PC = definitely need Threadripper.

 

You need to leave core 0 free for Unraid so whatever the core counts of your CPU, what is practically available for VM is n-1.

You then also need to take into account Ryzen architecture idiosyncrasy with CCX and CCD and latency penalty when crossing CCX / CCD.

So the TL;DR: with the 3900X, the best config for gaming is to have 1 full CCX per VM = 3 cores per VM.

 

Something you have not considered for practicality is USB hot-plug-ability. You will not be able to have USB hot plugs for all VM without additional USB cards (even Threadripper only has 2 passthrough-able onboard USB controllers). For some, that may be a show stopper right off the bat.

Yup, possible and not terribly hard but I will say that threadripper is certainly what I would recommend.  I initially got a 1920 and went to a 2950 after finding that the extra cores are almost a necessity if you want to run anything else- maybe a docker or two.  My wife and I built our beast to do our weekly lan party with another couple.  They don't have to bring anything over to play, and I don't spend all evening setting up their machines, getting updates, ect.  I also have 4 kids, so 4 gamers 1 cpu was a need more than a want- and boy has it come in handy after the lockdown.  You can check out my profile for build specs and challenges that I ran into.