Some basic VM questions

[dizmo]

Ok, so I've been playing around with the idea of making a computer for both me and my gf to use. Specs would be something along the lines of:

 

7950x

64GB RAM

2TB x2

RTX 4090

 

Would this work? Does it split 50/50, or do some cores need to be reserved to run the VM? If I was the only one using it, would I get the full power of the 4090, or does it always stay split between the two computers even if one isn't "on"? 

 

And, most importantly, how hard is it to set up a VM and is it pretty set and forget? 

[Levent]

Well vGPU is not even supported on customer level cards past Pascal so that wouldnt work. As far as CPU goes, for example if you assign 8 threads to a VM, that VM can only use 8 threads worth of CPU power, leaving rest to host and other VMs.

[Eigenvektor]

When you create a virtual machine, you can define how many (virtual) cores it gets, how much RAM, how large its virtual disk is and so on. It will only use these resources while running.

 

However, you cannot split a consumer GPU between host and VM. You need a workstation card that supports vGPU. On a consumer machine, you need two GPUs, one dedicated to the host, one dedicated to the VM ("GPU passthrough")

 

Setting up a VM itself is pretty easy. Create a new virtual machine, define which hardware features it has, insert a disk (.iso file) into its virtual drive, install the OS, just like you'd do with a real machine. For all intents and purposes, it behaves like a normal computer, so it'll need the same type of care (i.e. OS updates, driver updates, …). Since its hardware isn't real (outside the GPU, if you do passthrough) the drivers are generally part of the VM utilities you install/update.

 

Software running in the VM itself can often reach >90% of the performance it would on actual hardware. However, if you have intensive processes running on both host and VM at the same time, who knows how they will influence one another (the virtual machine won't use more resources then you give it, but the VM software itself also requires resources and software running on the host is not aware of the VM, so it can still try to use as many cores as it wants, no matter how many you've given to the VM unless you start to play with affinity masks).

 

It is typically much easier/cheaper to just build two actual machines. Plus, you now have a "backup machine" in case one of them breaks.

[Somerandomtechyboi]

1 hour ago, Eigenvektor said:

It is typically much easier/cheaper to just build two actual machines. Plus, you now have a "backup machine" in case one of them breaks.

^^^

and you wont have any issues getting banned on some games cause of running in a vm

 

If you want something with a similar effect you can house 2 pcs in one case, cheapest way would be to stick 2 cases together but i think there are some niche double sided cases that support 2 full systems (not an atx + mitx board on one side but 2 atx boards on the 2 sides of the case)