A friend of mine recently got a workstation with a threadripper processor, and apparently some games have so much trouble with the core count (lookin' at you, Far Cry) that you have to reboot into "game mode" with a substantial number of cores disabled.

But some other enterprising threadripper user worked around that by stuffing the game in a Linux VM to avoid the rebooting.

Crazy to think that a Windows game would perform better in a Linux VM under Windows than running on Windows natively, even if the reason is that it's effectively presenting the game with worse hardware that it understands how to use more effectively.

Funny, but not very fair: presumably a Windows VM with the lower core count would work as well.

Wouldn't that entail having an extra Windows license in order to be able to run the VM after the activation grace period has passed?

I believe that they got rid of the grace period in Windows 10. Now you can run Windows without a license key indefinitely, albeit with certain personalization features (e.g. color scheme, wallpaper) locked.

wait a darn tootin' minute there, are you telling me that paying for a Windows licence has become a cosmetic microtransaction?

Only for personal usage, businesses may still need to show licenses and with telemetry, it’s easier for Microsoft to find such usages. That said, with the switch to Linux servers, Windows is probably a declining business for Microsoft while Azure and Office are growing, hence “Microsoft 365” subscriptions.

I believe for non-production usage, Microsoft is okay with unlicensed or trial Virtual Machines and such. The idea being that if developers are testing their software in Windows, that’s better than the alternative (not testing their software in Windows).

Similarly, if willing to beta test versions of software, you can get Visual Studio for “Insiders” and test the Enterprise edition for free with a non-production license for as long as newer beta versions are made available. (Note: IANAL, this ain’t legal advice, read the terms and conditions on any Microsoft VMs or software installations)

Cosmetic macrotransaction.

There is a permanent Windows Activation message (white text on transparent background) in the lower right part of the screen which my brain already blocked so it's not distracting at all. I only notice it after taking screenshots.

Windows server at least will randomly reboot until you get a license, let me tell you how fun that is to figure out.

It may, but then you would need to purchase two Windows licenses if you want to keep the host OS Windows.

Can you share a GPU to a windows VM?

I'm surprised that you can't just lock the game's threads to a smaller number of cores, but I can imagine the DRM some games ship with preventing you from doing it. Booting up a VM with its core count limited is a clever workaround... I'm guessing a Windows VM would have reduced GPU performance because of the way pass-through works.

You can shutdown/disable cores on the fly. There is a nice gnome-shell extension for that. Shouldn't that do the trick ?

AMD says

Game Mode is a new feature in AMD Ryzen™ Master that reconfigures the platform in two key ways:

• It temporarily disables half of the CPU cores, which turns the AMD Ryzen Threadripper 1950X into an 8C16T device (like the AMD Ryzen™ 1800X) and the 1920X into a 6C12T device (like the AMD Ryzen™ 1600X). For the truly technical, this is a 4+4 CCX configuration on one die. This ensures the game encounters the number of cores it was truly designed to handle. Please note that Game Mode does not disable SMT.

• We tell the OS to use a Local Mode (NUMA) memory, which keeps a game and its memory footprint inside one CPU die and the locally-connected DRAM. This minimizes several key latency points in the system, which most games love.