It’s well worth installing SteamOS in VirtualBox. That’s what I did — and I’ve written a guide on how to install SteamOS in VirtualBox, if you feel like doing the same.
Grab the latest version of VirtualBox and install it (it may take some time.) Get
SteamOSInstaller.zip
from Valve. Download ISO Creator and install it.
Extract
SteamOSInstaller.zip
into its own folder. Open ISO Creator. You can name the ISO whatever you like, just make sure you save the ISO in a sensible location. Select the folder that you extracted the zip file to. Hit Start and wait a minute or two while the ISO is created.
Now open VirtualBox. This bit is somewhat complex with lots of little steps and gotchas, so be careful. Create a New virtual machine. Give it any name. Type = Linux. Version = Debian (64 bit). Click Next. Pick any amount of memory (1GB is sensible if you’re just going to fool around; 4GB if you want to try out DOTA 2 or something). Accept the default options on the next few pages of the wizard, and choose “Dynamically allocated” when prompted. Pick a hard drive size of around 50GB.
Once you’ve created the virtual machine, select it on the right hand side and enter Settings. Click System and select Enable EFI. Click Display and select Enable 3D Acceleration. Slide the Video Memory slider up to 128MB. Click Network and select Bridged Adapter from the Attached to drop-down. Click USB and use the + icon on the right to add your USB keyboard and mouse (if applicable).
Finally, head to Storage, click the optical disc icon under Controller: IDE, then hit the optical disc icon on the right hand side (see image). Click Choose A Virtual CD/DVD Disk File, then find the ISO file that you made earlier. Click OK to return to the main VirtualBox interface.
If you receive an error at this point, it’s probably because you haven’t enabled virtualization in BIOS. Enabling virtualization is beyond the scope of this how-to, but if you Google the name of your motherboard and “how to enable virtualization” it’s pretty easy.
Start the SteamOS machine!
Now, click Start and pray. If all goes to plan, you’ll be greeted with a prompt that looks like the image above. After
2.0 Shell>
type the following: FS0:\EFI\BOOT\BOOTX640
. If you can’t type the backslash (\
) for some reason (I couldn’t), change your system’s keyboard to US layout, then use the On-Screen Keyboard app to type the \
. Press Enter, and you should be greeted with the first sign that you’re installing SteamOS.
From this screen, press Enter to begin the automated install. Don’t worry about the WILL ERASE DISK! warning — VirtualBox prevents SteamOS from changing anything on your local filesystem.
The installation process is automatic and takes a few minutes.

Once the automated install is complete the system will reboot and you’ll be greeted with the above screen. Select the second option, recovery mode. The system will boot up and you’ll end up at a Linux command prompt.
Install VirtualBox Guest Additions
So that SteamOS is actually usable as a virtualized OS (clipboard sharing, shared folders, better mouse pointer integration), you must now install VirtualBox’s Guest Additions. From the command prompt type the following commands, pressing Enter after each one.
mount /media/cdrom
sh /media/cdrom/VboxLinuxAdditions.run
This will take a few moments to install, then type
reboot
and press Enter.Almost there…
This time around, don’t touch the GRUB bootloader and your system will automatically boot into a graphical interface — SteamOS! Well, almost. You’ll be greeted with a login prompt. Keep Default Xsession selected. The username and password are both
steam
.
For some reason, the Return To Steam icon on the desktop doesn’t work; you need to click Activities in the top left, then Applications, and scroll down to Steam. The Steam app will update, and then you’ll be greeted with the usual login prompt. Log in, hit Big Picture in the top right corner… and voila! You now have a (virtualized) Steam Machine!
From this point on, you’re pretty much on your own. I haven’t explored SteamOS much yet, but to be honest it doesn’t look like there’s much to discover: Right now, I think it’s just Debian with Steam pre-installed. It’s probably a good idea to have SteamOS installed now, though, so that you can take a look at exciting features — such as local game streaming — when they’re rolled out in 2014.