Real World QEmu-kvm Gaming Performance

A user named Zoltan made an excellent post about if you want everything but on Linux. As a gamer and a Microsoft student i need to be able to play my video games but also use Internet Explorer for my class labs and those two reason are why i haven't switched over to Linux. But with my introduction to "QEmu-kvm" i can see the light again.
So before i make the switch i want to be clear that i can get al least 95% of my computers gaming performance by gaming on windows inside of QEmu-kvm?
Thank you to anyone who takes the time to help me out.

also interested in this, unfortunately there is almost no info about the performance :/, hope someone knows some benchmarks

I found this video but its not very informational

yup, i also saw one for chivalry, its probably because not very many people use kvm/qemu for gaming purposes, its mostly for business usage

There is a fair amount of info out there about gaming on KVM and using hardware passthrough to a graphics card, quite a bit on this website/forum too.

One guide I found useful was here: http://www.pugetsystems.com/labs/articles/Multiheaded-NVIDIA-Gaming-using-Ubuntu-14-04-KVM-585/ Also read their blog poist about gaming on a multi-headed VMware platform, it's fascinating.

If virtualising with hardware passthrough gaming performance should be near to bare metal, within a few FPS. Some people also report performance boosts on some games, I have even read claims of over 20% but without any evidence. In my experience this sounds unlikely but may occur with CPU limited games or when you are running a low resolution/detail setting. I have had certainly had games running natively on Linux with higher framerates than on Windows until I ramp up the resolution/detail settings.

Thank you for sharing that link with us. Right off the bat in hardware requirements I noticed that the CPU needs to support virtualization, my CPU is a I5 4670k and I don't think it supports virtualization does this automatically disqualify me from using this method to gameM

Unlocked Intel do not support VT-d which you need to run Windows like this. The non-k variants may support them. All AMDs support this.

I was pissed about this when I found my 2500k did not support it. Will consider red team in the future.

So all AMD CPU support this?

I am so let down now.

Yes, you need a motherboard that has the proper settings in the bios. Asus apparently has been breaking theirs, people have had the best luck with AsRock. You are looking for Amd-vi and IOMMU.

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You need VT-d to do pass-through, which your CPU does not have: http://ark.intel.com/products/75048/Intel-Core-i5-4670K-Processor-6M-Cache-up-to-3_80-GHz

The latest K-series does support it so not all unlocked versions are ruled out. eg: http://ark.intel.com/products/80807/Intel-Core-i7-4790K-Processor-8M-Cache-up-to-4_40-GHz

So i do have an asrock mobo with a i5 4670k, so theres a chance I'll find that option in my bios when I get off work?

Your motherboard might support it but that does not make up for the lack of VT-d on the processor.

^ this. For some reason Intel has decided that binning features into different products is a good idea for consumers. That i7 4790K does support it according to wizard's link, but the Devil's Canyon line was a well received/liked line anyway from what I remember.

That's so lame that post about "what if I want it all" really got me excited

It is really cool, just wish I knew about it before I built my computer 3 years ago.

Same for me. if i knew about this i wouldnt have gotten the sabertooth 990fx gen3/r2 (doesnt support it while the 990fx r2.0 does) and i would have gotten an AMD Gpu instead of my GTX 780

Same for me :/
Otherwise, the 2500k is one of the best price/perfomance CPU to this day.

If your CPU or Mobo doesn't support hardware pass through I wouldn't be too down. You have options;

Configure a dual boot system and start gaming natively in Linux. You can still create KVM based VM's running Windows if you are learning about Windows or need to run Visual Studio etc. and only boot into Windows for the games that either are not on Linux or don't readily work with WINE.

or,

If you have Windows 8/8.1 professional you can also go the other way and just run Linux on Hyper-V VM's. The latest versions of Ubuntu and Suse know if they are running on Hyper-V and have the correct drivers in their kernels. I've done this quite a bit and performance is acceptable. If you don't have Hyper-V download Oracles free Virtual Box if you just want to dabble in Linux before installing it properly.

On the bright side of not having hardware passthrough, think of all the time you will save. Getting it working properly can be a pig :-)

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Thank you for that information, I think I'm just going to install Ubuntu on its own drive while my other drives are disconnected so that Grub doesn't screw with my master boot partition on my windows drives and then I'll just use the bios to lick what drive I want to boot to. Will that work?