Until the necessary pieces have fallen into place, here's a temporary solution to run the game.

What a fool I am. I haven't used Windows for years and apparently forgot that little crucial step.
Sorry about that. Trust me it's more than a little frustrating.

The data is in

Long story short it’s apparently a limitation in the current Nouveau driver since I noticed that lowering the refresh rate to 120 Hz (on 1440p) before booting works around the problem.
After installing NVIDIA’s proprietary driver on the installed system it's possible to renegotiate the refresh rate without the monitor blacking out, including to 144 Hz.

@bvdlingen
Kindly mail him and ask

This email address can be obtained by using the email referenced on the Press Center page and removing the anti-spam bits. I'm not going to be looking at the Phabricator database to get people's email addresses so commenting alone will not help you.

@presianbg The tools to create an adapted Solus ISO was removed since it was abused for evil.

The workaround for new NVIDIA cards to install nvidia-glx-driver-current after setting nomodeset stopped working recently.
Some essential packages are unfetchable

Apparently it is possible to have more fine-grained control, by holding the shift key while adjusting the volume. I personally would prefer the fine-grained control to be the default behavior, alternatively there is an issue of discoverability.

In the associated README however the old products are listed along with the new as you may have seen.

I don't know the technical limitations.
But since Intel intend to replace Beignet I would expect to have only one of them installed at a time to avoid potential conflict.

Ideally as a service to the users they would be suggested to use this package instead of Beignet and vice versa depending on their processor.

Thank you for the helpful feedback. I've filed an issue over there.

Any useful clues in the latest fedora build?

Have been able to verify that this is not an issue in recent updates. It still works after removing the Driver "evdev" line and rebooting.

Status update
./gpuvis is launching fine ✓

Is an out-of-tree patch still interesting for an optional kernel?

Here is a torrent link to download Audiophile Linux if someone wants to investigate and find out if there is anything interesting to learn from it.
This should potentially be faster than their free hosted download.

OpenCL seems to work with Nvidia now. Intel is detected with Beignet installed but has errors.

Managed to get the keyboard working with evdev installed by manually adding the line

sudo libinput debug-events

With gavandor's fix, https://dev.solus-project.com/T3752, error 306 is gone and VR is now live and running on Solus.

Thx, that worked well! vulkaninfo can now run and the Talos Principle is able to switch to Vulkan graphics in-game.
10_nvidia_wayland still gives errors but I'm guessing that has more to do with the current state of Wayland support.

Same problem with nvidia-glx-driver 384.90-175

Maybe this could have helped before doing the final build? https://dev.solus-project.com/T3663

The driver revision might be of interest
nvidia-glx-driver 384.59-164

Other changes
./vrcmd alternately spams the following

A small update

Will attempt a qualitative argument. The clones I've tried, even the nicely integrated one here, including on Android don't come close to the color filtering quality of f.lux. The clones give the impression that it's just a linear red/yellow color filter slapped on top of the screen. f.lux. has got it down to a science and for example understands that light in the green spectrum affects wakefulness as well. Also movie mode is a very useful compromise when you want to watch a movie without turning it off or having too awful colors.

Removed the nvidia kernel modules (.ko files) for the active kernel. Still no luck.
Next stop: attempt to disable kernel mode setting to be able to use the nouveau driver again.
Had trouble accessing the efi menu though. (Supposed to press some special key to access it?)

Apparently there is already a distributed compiler, Icecream, which is used for building Chromium.
It would be cool, pun intended, if it was possible to opt-in to something like this in Solus and act as a remote build server when under light loads.

Can verify the GTX 1080 Ti runs Portal 2 well

Guess nvidia-opencl-icd should be available after installing the driver??

So the nvidia-glx-driver reached stable sooner than I expected :-)

SVP doesn't output any warnings anymore it however outputs this:

My understanding is that you can patch existing kernels.
The Real-Time Linux Wiki should give an overview.
The RT PREEMPT HOWTO should do the trick.

Did encounter this recently again on a laptop when attempting to log in after automatic log out.

FWIW I agree that this probably wasn't caused by keyboard mashing and haven't encountered it anymore.

Yes

The Zimg v2 linked below vapoursynth's Linux and OS X compilation instructions seems up to date.

It seemed obvious to open it for investigation, was just trying to help. Not my intention to offend anyone by reopening the issue.

This indicates it is possible. Could probably make the proprietary version redundant as a third party application.

Right, let me rephrase that. Any interested user might want to request one of those alternatives instead.

Maybe one of these will do instead?

Any progress on TuxTyping? Have it on another distro and the kids like it. The sound effects though are pointless. I only recall a sound when switching menu items. Personally I would prefer to have it available now on Solus without sound if possible.

Quality education game. The kids love it!

Seems reasonable

Thanks, it works after installing the 32-bit driver. The solution is not immediately obvious though. Is there something planned to simplify the experience for the user?

It seems the users have very likely triggered some keyboard shortcut to put the system in this state.
It seems like something that probably shouldn't happen anyway, assuming there is no obvious way to resolve it.
Any guesses about which shortcuts could have been mashed on the keyboard?