Tutorial for passing through a Nvidia RTX graphics card to a Windows 10 virtual machine using a modified VBIOS
Recently I replaced my old NEC MultiSync 2690 HD screen for a HP DreamColor wide gamut screen with a 2560 x 1440 pixel resolution. The Nvidia GTX 970 GPU I used, though still perfectly capable at HD resolution, is likely to get challenged by higher resolutions. Moreover, the new Nvidia Studio driver doesn’t support models before the Geforce 1000 series, and I do want the 30 bpp (bit-per-pixel) support that this driver provides. Time for an upgrade – the Gigabyte RTX 2070 Super GPU.
I’ve already written a detailed tutorial on Windows 10 kvm VGA passthrough based on QEMU version 2.11. Years have passed and recent distributions like Ubuntu 20.04, Linux Mint 20, or Manjaro come with QEMU 4.0, 4.2 or 5.1.
It wasn’t easy this time. Don’t get me wrong – the VFIO passthrough part, though challenging in some ways, went quite well. All in all I’m pleased now with the results. Here the Passmark 9.0 benchmark as uploaded onto their database (for more details, click the frame below):
I’ve been contemplating a PC upgrade for more than a year (see my post here). At first I considered staying with Intel and getting an i9-9900K CPU with integrated GPU on a Z390 motherboard.
Along came the AMD Ryzen 9 3900X that topped the benchmarks, including the Adobe Lightroom and Photoshop benchmarks (to be precise, it ranked #4 in the Adobe Lightroom benchmark, and a narrow #1 in the Adobe Photoshop benchmark). These good news about the AMD Ryzen 3900X were soon followed by reports about BIOS issues and VFIO incompatibility. At the very least, it looked like VGA passthrough was more challenging.
A year ago I wrote about the 2D graphics performance impact of the Windows 10 (1803) update inside a virtual machine. As it turned out, the performance impact was related to the Spectre vulnerability patch that Microsoft had introduced. However, the same patch had practically no performance impact on a Windows 10 bare-metal installation.
When running a VM with GPU passthrough, that GPU should be bound to the VFIO driver. To make this happen, we need to prevent the regular graphics driver from binding to the passthrough GPU and instead bind the vfio-pci driver.
Before you get your hopes high, this post is not (yet?) a tutorial on creating a Windows 10 virtual machine using the Virtual Machine Manager (virt-manager) GUI. It should have been, though. I spent the better part of a week trying to configure and install a Windows 10 VM that delivers the performance that I’m used to.
As it turns out, it was a failure. Don’t get me wrong, I did manage to configure and run Windows using virt-manager and virsh. I even installed it multiple times, changing the configuration to what I hoped would improve performance. But whatever I tried, I never got even near the speed and snappiness that I achieve by following my tutorial using a start script.
Back in 2012 I built a PC around the Intel i7 3930K 6-core/12HT processor which I have been using ever since. While it’s still a strong PC, especially with the upgrades (GPU, SSD) I made, I’m starting to feel that editing photos isn’t as snappy as it used to be. I am also curious in how well the new generation of CPUs lend themselves to VGA passthrough. In short, I’m considering building a new PC. Continue reading “New PC Build”
You may wonder what’s wrong with this fellow (meaning me, the author). Has he completely lost his mind when he proposes a Linux virtual gaming machine? Before you discredit the idea, let me explain. Continue reading “Linux Virtual Gaming Machine”