Can two people simultaneously use the same computer?

[IAgreeToTheTernsOfService]

My wife and I are both gamers and constantly want to use our one powerful desktop. Is it possible that a single desktop can be configured to allow both of us to use it at the same time, or is that a pipe-dream?

[DaveLembke]

Its far easier to just have 2 computers.

The biggest issue is that the computer expects only one keyboard and mouse to be in use. So even with 2 displays and a game set to each display and plenty of CPU GPU and RAM to run both at the same time, the system is going to only want to focus on one game and keyboard and mouse input at a time, so with 2 keyboards and mice you would be constantly competing for controls as the system expects a single user.

[Geek-9pm]

Right.
What he says is true. For a home user it makes more sense to just buy another computer. A true multiuser computer for use in your home is just not in the future.
Years ago, before the cost of the hardware went down, there were methods used to allow network users to share the resources of a central server. This is commonly done in systems based on UNIX. But the performance level is very low for each individual user.
You might read about efforts to make a multi-user Windows server, but this is only in the early stages and is not going to be of any help to the individual home user. It is intended for the people that operate a central server in a company that has several users tied into terminals.
It is much more practical for the home user to just get another computer. And when that happens you then will fight over which one gets to use the newer computer.
So in the final case you will have to buy two brand-new computers and sell your old one.

Really, I'm just trying to help. 

[Quantos]

You can't have two people playing at the same time with GPU technology.  If you want to compete or play together either get two consoles or two PC's.


And it doesn't matter what the OS can do.  I'm going to go out on a limb and predict that this will NEVER be a thing.

[gorge441]

My wife and I are both gamers and constantly want to use our one powerful desktop. Is it possible that a single desktop can be configured to allow both of us to use it at the same time, or is that a pipe-dream?

I think NO. You need another PC.

[BC_Programmer]

You can do this with Virtual Machine software. Though it is non-trivial. You need to install three graphics cards (two 'gamer' cards and one for admin), the system itself uses the "third wheel" card, and you create two VMs, both of which are given hardware passthrough (using VT-d or similar) to one of the two capable graphics cards. Connect a monitor to each card and you get each VM's output; connect an extra pair of keyboards and mice and then use the VM software to connect one of each to the Virtual Machines.

[Quantos]

You can do this with Virtual Machine software. Though it is non-trivial. You need to install three graphics cards (two 'gamer' cards and one for admin), the system itself uses the "third wheel" card, and you create two VMs, both of which are given hardware passthrough (using VT-d or similar) to one of the two capable graphics cards. Connect a monitor to each card and you get each VM's output; connect an extra pair of keyboards and mice and then use the VM software to connect one of each to the Virtual Machines.

Except you can't game on a VM

[BC_Programmer]

Except you can't game on a VM

What I described has been used by people to create single PC builds which provide multiple workstations and users can game on them simultaneously. The hardware passthrough/Directed I/O is what makes it feasible. It would require more than one graphics card, however.

[Engineer.AI]

Although I am inclined to agree with the community on this, it is definitely sad that this isn't a reality we live in. Makes one think of the whole concept of a "PERSONAL COMPUTER" in detail. I mean, a sophisticated device (expensive at that), for just one person at a time? Something like a shared GPU, split RAM, co-shared data, etc. could be utilized to bring this to fruition maybe. A person like me, would love that. I engineer AI, but for this one reason, I wish I was a CS.

[Quantos]

What I described has been used by people to create single PC builds which provide multiple workstations and users can game on them simultaneously. The hardware passthrough/Directed I/O is what makes it feasible. It would require more than one graphics card, however.

What game and what performance level?

You would need to allocate the minimums for each game in each VM.  That's not practical from any angle.

[BC_Programmer]

What game and what performance level?

The one I saw was done back in 2015, using 32GB of RAM, a 980GTX and a Titan X Graphics card, and an Intel 5960X (An 8-core processor with hyperthreading). It used "Limetech Unraid" to provide the virtualization featureset. Both virtualized systems were playing the game simultaneously and appeared to run the title competently, with the benchmarks they ran giving something like 100+FPS averages in the title, which I think was Star Wars Battlefront II.

You would need to allocate the minimums for each game in each VM.  That's not practical from any angle.

While it was excessive at the time, Nowadays for a "powerful" Desktop, I don't think 16GB or even 32GB is a particularly heavy "ask" of a system. And with AMD Ryzen CPUs having a large amount of cores, there is a lot to go around, even setting aside 2 cores for the host OS. The reason the idea isn't practical (And why I noted it as being non-trivial) is largely because you don't just install a program and magically get one PC to be two, and it requires some rather involved setup. It's not a case of installing VMWare or VirtualBox and checking off a few options. The one I saw used Unraid but maybe it would work with VMWare vSphere.

[Quantos]

The one I saw was done back in 2015, using 32GB of RAM, a 980GTX and a Titan X Graphics card, and an Intel 5960X (An 8-core processor with hyperthreading). It used "Limetech Unraid" to provide the virtualization featureset. Both virtualized systems were playing the game simultaneously and appeared to run the title competently, with the benchmarks they ran giving something like 100+FPS averages in the title, which I think was Star Wars Battlefront II.

Very cool, I know there has been a little bit of headway made, but wasn't aware it had started back that far.  It must be using that EMA(Explicit Mulitple Adapters) addition to DX12 that 'Ashes of the Singularity' uses.

While it was excessive at the time, Nowadays for a "powerful" Desktop, I don't think 16GB or even 32GB is a particularly heavy "ask" of a system. And with AMD Ryzen CPUs having a large amount of cores, there is a lot to go around, even setting aside 2 cores for the host OS. The reason the idea isn't practical (And why I noted it as being non-trivial) is largely because you don't just install a program and magically get one PC to be two, and it requires some rather involved setup. It's not a case of installing VMWare or VirtualBox and checking off a few options. The one I saw used Unraid but maybe it would work with VMWare vSphere.

I'm going to have to take another look at this subject with a fresh perspective, should be interesting.

[Quantos]

It took a loooong time to test that, and for all intents and purposes you CAN'T game on a VM with any game that actually requires it's own GPU.  There are no GPU passthrough drivers.  I've tried this with a variety of games, League of Legends, Valorant, CS GO - they all recognize that they are in a VM and won't run.  I've also tested with different GPU combinations to see if that would affect it.  Dual 970's, 970 and 2070, both of those - one at a time though - with an rx 570.   

[BC_Programmer]

I don't think it's possible on any realistically consumer-available virtualization software, which is why I said it wasn't realistic for the OP. I think it requires an enterprise-level hypervisor, like vSphere. Only one I've seen actually used is Unraid.

As I understand, The way software detects it is running in a VM is usually by checking hardware for virtualized device names, or by checking BIOS copyrights and stuff. Most Virtual Machines virtualize that information. (eg. for VMWare devices like VMWare SVGA II, VMWare network bridge, and a bunch of stuff software could check for like VMWare Tools) Unraid- at least from what I can find- has the ability to pass-through the "real" information to Virtual Machines instead. Which is intended largely to deal with these sorts of software checks. I think games do that to prevent hacking or cheating since that could be done via a VM.

I wish I could find somebody else that did it, because they annoy me, but LinusTechTips did a "7-gamers, one CPU" system doing more or less what they did with the 2-workstation setup. (I  think that video largely covers the hardware, and a follow up has all 7 being used in Crysis 3. Allegedly that game has VM detection which (presumably) didn't get tripped because of how they were setting stuff up.

of course, it could all be smoke and mirrors, but as much as I can't stand the channel I don't think they've outright lied like that before. And I'm pretty sure this sort of thing is done for enterprise stuff, for things like VPS setups, so it doesn't seem like a big leap that the same approach could be taken to spin out separate gaming setups.

EDIT: SnapRAID might be a free/Open Source alternative? It seems to have hardware passthrough though all I can find relates to it passing through Disk controller cards.

[Quantos]

Yeah, it just took me quite a while to exhaust each of the possible solutions that I could come up with for it.  I wanted to be thorough, I think it was my laziness that really dragged it out too though   

I don't think it's possible on any realistically consumer-available virtualization software, which is why I said it wasn't realistic for the OP. I think it requires an enterprise-level hypervisor, like vSphere. Only one I've seen actually used is Unraid.

I suspect that you could be right about vSphere, it will run bare metal - from what I've read about it.

As I understand, The way software detects it is running in a VM is usually by checking hardware for virtualized device names, or by checking BIOS copyrights and stuff. Most Virtual Machines virtualize that information. (eg. for VMWare devices like VMWare SVGA II, VMWare network bridge, and a bunch of stuff software could check for like VMWare Tools) Unraid- at least from what I can find- has the ability to pass-through the "real" information to Virtual Machines instead. Which is intended largely to deal with these sorts of software checks. I think games do that to prevent hacking or cheating since that could be done via a VM.

I've since talked to someone at Riot and he said the exact same thing.

I wish I could find somebody else that did it, because they annoy me, but LinusTechTips did a "7-gamers, one CPU" system doing more or less what they did with the 2-workstation setup. (I  think that video largely covers the hardware, and a follow up has all 7 being used in Crysis 3. Allegedly that game has VM detection which (presumably) didn't get tripped because of how they were setting stuff up.

of course, it could all be smoke and mirrors, but as much as I can't stand the channel I don't think they've outright lied like that before. And I'm pretty sure this sort of thing is done for enterprise stuff, for things like VPS setups, so it doesn't seem like a big leap that the same approach could be taken to spin out separate gaming setups.

I agree, I don't have much patience for Linus, but I'm positive that he has more integrity than that.

EDIT: SnapRAID might be a free/Open Source alternative? It seems to have hardware passthrough though all I can find relates to it passing through Disk controller cards.

That's about all that I was able to find for most situations is USB or PCI passthrough.  I have seen a lot of people refer to software that will enable a GPU passthrough - I haven't been able to actually locate any though.


I DID have a LOT of fun trying what I could with it, and I'm pretty sure that I've learned a few more things about hypervisors too.