I agree, it must be the video card.

It's hard to develop open source drivers for new cards quickly. and SteamOS (Debian in general) lags behind a little incorporating the newest kernel releases for stabilities sake.

I'd say either wait for a newer installer or try one of the user made alternative installers, such as Stephensons Rocket which try to incorporate more driver options like AMD's proprietary drivers.

That doesn't look like a HW issue to me. It's failing installing files. As if something was wrong with the installer. Or the target filesystem.

Check the installer, try to install another way?

Just a shot in the dark but does your UEFI Bios have secure boot or video mode options you could play around with? You could also try removing the load_video and fgxmode lines.

I had the same problem a long time ago with a new UEFI system and any Linux distro I tried to boot. Eventually it just fixed itself with a newer kernel versions. But the suspect was some quirk with the UEFI implementation.

First thing I'd suspect is the graphics. Have you played around with the vm's hardware setup?

Otherwise you want to edit the boot entry for SteamOS in grub and remove quit splash and fbcon=... bits at the end of the kernel line.

My bad, haven't gotten in there in a while. Yeah, remove quite and the fbcon=.. bits. You can boot into command line mode to troubleshoot if you want by adding systemd.unit=multi-user.target or resue.target. (used to be you just added a 1 or 3)

Cheez... wat?

You'll need to hold down right-hand shift to get into grub. Then turn on boot messages by pressing e at the SteamOS boot entry and removing splash quit vt-handof from kernel line.

It's dual graphics...

The easiest thing would be to turn off one or the other in bios. Then set something up to switch between them in the OS. (Bumblebee..?)

Try removing vt-handoff or adding a 1 at the end to go into single user mode, for debugging.

Right, I didn't watch it past a few seconds, my bad. Hate Youtube videos other than Red Letter Media's and Highlight Reel.

Now that I think of it. A long time ago, I had a similar issue where booting stopped at a black screen. It was a bug between the kernel and motherboards UEFI video mode. Fixed it by pressing e to edit Grubs boot entry and removing any quiet and splash line. I forget what they are on the installer's. So you might want to post a pic of that if it doesn't work.

You could try an alternative installer called Stephenson's Rocket. It's an actual iso image that you can dd or whatever on the usb stick.

Lets back up to those videos, Did you ever pick the UEFI option in the Grub menu? Because, I think that's the right one. SteamOS must be installed in UEFI mode.

Otherwise, your latest screenshot is the hard drives Grub which is useless now.

Man, recovery really messed your system up.