Steam OS UEFI Workaround Method 3
The following is a third method on getting SteamOS on a non UEFI motherboard:
mkdir /media/usbstick mount /dev/sdX1 /media/usbstick (replace X with the proper letter for your USB stick) grub-install --no-floppy --root-directory=/media/usbstick /dev/sdX (replace X) or (for grub 2) grub-install --force --no-floppy --boot-directory=/media/usbstick /dev/sdX (replace X)
[excerpt from forum]
Adapt boot/grub/grub.cfg from the SteamOSInstaller.zip and put it to your usb stick. Copy everything except the boot folder from SteamOSInstaller.zip to your usb stick. The usb stick should now be ready.Be warned that even the “Expert install” option WILL format your hard drive without warning! This is what happened to me, and I’m currently recovering the partitions…
- These steps are VERY important, as this installation method is of the type Valve considers a “Custom Installation.”
- After installation is complete, log onto the resulting system (using the Gnome session) with the predefined “steam” account. The username is “desktop” and the password is “desktop”
- Open the “Home” folder and run the file “post_logon.sh” Choose to “Run in Terminal.” This is paramount for big picture mode.
- Enter your sudo password of “desktop”
- Installation will commence and reboot the PC. (you may have to reboot twice)
- Note: if for some reason the reboot fails to find the kernel, hit “return” and choose the 1st default GRUB boot entry. The OS will then load.
- After picking “Gnome” and logging on with the Steam account (password “steam), hit the “Return to Steam” shortcut on the desktop.
To boot from USB, download this , extract plpbt.iso and boot from that, it’ll allow a USB boot. Note that ‘Enable USB 2.0 (EHCI) Controller’ must be DISABLED.
“I am stuck on now is “Run steam, accept the EULA, and let it bootstrap. Logoff the steam account”.”
run steam from a terminal for it to work, once I was on the login screen, I quit steam then logged out the steam user, then jumpped into desktop and executed the script.
Ran the script, it rebooted into capturing recovery partition mode then something failed and threw me into (initramfs) prompt. I rebooted into “normal” mode again and after the loading finishes I get stuck with a black screen.”
This was caused by having two screens attached. Disconnecting one of them helped.
“I’ve noticed it sometimes seemingly dismounting my USB drive, not entirely sure what causes it, try it again and see if it’s any better… There may be a driver issue otherwise, I’ve only done my testing in VirtualBox.”
If you Ctrl+alt+F4, the logs might explain why it’s not working.