If you follow gaming news, you've probably heard of Steam OS--Valve's new operating system for dedicated gaming PCs. It's Linux-based, designed for use in the living room, and completely free.

Unfortunately, it'll be a while before Steam OS is ready to pose a challenge to Windows on gaming computers. Because it's Linux-based, the significant majority of the games in Steam's catalog won't run on SteamOS--though Valve's using technical trickery to work around that--and the software itself is still in beta testing. The first "Steam Machine" consoles from PC manufacturers aren't expected to ship until late this year.

So are you out of luck if you want to see what SteamOS is like? Not at all. If you've got 30 minutes to spare, you can get SteamOS up and running in a virtual machine, which will let you explore Valve's operating system without ever leaving the comfort of your Windows desktop. The installation process is pretty convoluted, but you won't have any trouble if you follow our step-by-step guide.

Note: SteamOS is beta software under active development. The steps in this guide were written for the latest version of SteamOS (update 96), but may not be accurate for future versions of the software. Consider yourself warned!

Download SteamOS and VirtualBox

There are two pieces of software you'll need before we can begin.

At about 1GB, SteamOS is a pretty big download so you should start that first. If you Google "Steam OS," the first few links go to outdated installation files. The file that you want is available in the Steam Universe group on Steam's forums. (Future SteamOS updates will be available on the group's homepage.) Click on the "installer ISO and ZIPs" link, then select to download the SteamOSDVD.iso file. This file simplifies the installation process substantially over some earlier releases, so even if you've downloaded SteamOS in the past, it's worth downloading the newest version.

You'll also need VirtualBox, the free virtualization software from Oracle.

Create a virtual PC

Now, you'll use VirtualBox to create a virtual computer onto which you'll install SteamOS. If you've never used a virtual PC before, you can think of it as a "computer simulator." It uses some of your computer's CPU cycles, memory, and hard disk space to create a computer-in-a-window that acts just like the real thing. It can even run an operating system other than Windows, such as Ubuntu or (in this case) SteamOS.

Install VirtualBox--leaving all the default options selected--and when it's finished, run the program. Click on the light blue New button in the upper left corner and a new dialogue box will open up, which will walk you through the setup process.

On the first screen, you're asked pick a name for your system and to choose what type of operating system it will run. Pick whatever you want for a name, and choose Linux from the type dropdown menu and Debian (64 bit) from the version list.

On the next screen you'll choose how much of your system memory the virtual computer will use while running. Choose less than half of your total system memory--one or two gigabytes should be fine. Of course, most games call for at least 2-4GB of memory these days, and Valve recommends SteamOS systems have 4GB-plus of memory, but that's to play full-fledged modern games. VirtualBox isn't going to be the right kind of environment to run those. We recommend you pick a more hardware-forgiving game, such as Monaco or Superbrothers, and consider this virtual machine endeavor more of a test drive for the operating system itself.

Next you'll be asked about a hard drive. Choose to create one now, and then on the next screen, leave the first option (VDI) selected, and click Next. On the next screen, leave the Dynamically Allocated box checked and hit Next again. Finally, you'll be asked to pick a size for your virtual machine's hard drive. Note that you won't actually be giving up all this hard drive space right away--the dynamic allocation option you selected earlier means that virtual hard drive space is only created as you actually use it. The amount you specify here is just the maximum amount the virtual machine will ever be allowed to use. So go ahead and pick a fairly large value, such as 40 or 50GB.

Configure the SteamOS virtual PC

With that, your virtual SteamOS machine is created--you can see it in the column on the left side of VirtualBox. Before we "power on" the virtual machine for the first time, there are a few more settings we need to tweak.

With the SteamOS machine selected in the left column, click on Display in the main part of the VirtualBox window. In the display options window that opens, drag the Video Memory slider all the way to the right, and click on the box labelled "Enable 3D Acceleration." Next, click on the System options button and check the box labelled "Enable EFI."

Next, click on Network, and in the NAT dropdown box select "Bridged Adapter." If you receive an error warning, leave it as the default "NAT" option.

Lastly, click on the Storage options button. Here we'll load up the ISO we downloaded earlier, so our SteamOS virtual PC can boot from it. In the box marked Storage tree, click on the entry with a little CD icon that says "Empty." Then, click on the second CD icon at the very right of the screen, next to the CD/DVD drive dropdown menu. Select "Choose a virtual CD/DVD disk file" from the context menu that opens under the CD icon. Browse to the ISO file you downloaded in step one.

Install SteamOS

Finally, we can start up our virtual machine and install SteamOS. Frankly, this process is a bit confusing and involves a fair amount of manual tweaking as you go. Follow along with each step, and you shouldn't have any problems getting into SteamOS.

Double-click on the SteamOS machine's icon in the left-side column of VirtualBox. A new window will open, which acts as the "monitor" for your virtual PC. After just a few seconds you'll see the SteamOS installation menu in it. (If you see "Error: Prefix not set," just wait it out.) Choose the first option, "Automated Install," using your keyboard. It says it will erase your disk, but don't worry! That's only true inside the virtual machine. Your actual hard drive will be fine, which is why we're doing this in a virtual machine to begin with.

After you click it, the system may seem to freeze for some time, then the SteamOS installer will begin, and automatically install all the files it needs. This process will take several minutes. When it's done, the machine will reboot, and briefly give you the option to start in recovery mode. If you don't, the virtual machine will simply go to a blank screen. If this happens, reset the virtual machine (Machine > Reset), and choose to start in recovery mode while the option is available to you.

You'll now see a command prompt, where you'll have to enter several commands. First type apt-get purge ".*nvidia.*" and hit enter. Some stuff will scroll by, and you'll be asked for a "y/n" confirmation. Type "y" and hit enter.

After more furious scrolling of text, you'll again find yourself at the command line. Enter dpkg-reconfigure xserver-xorg and press enter. If you don't get any confirmation at all, but just see another command prompt, that means it worked.

Now, we'll need to install VirtualBox guest additions--a suite of software that essentially allows the Debian-based SteamOS to function in a virtual environment. To do that, follow these steps:

First, click on the Devices menu at the top of VirtualBox, and then click on Insert Guest Additions CD Image. (You won't receive any confirmations that you've done so.) Next, type in mount /dev/cdrom/media/cdrom and hit Enter. (Note the space after "mount"!) The virtual machine will say something about mounting read-only, but that's fine.

Next, enter the command sh /media/cdrom/VBoxLinuxAdditions.run--once again, note the space after "sh"--and hit Enter again. Lines of text will scroll up for a few seconds as the virtual machine installs the Linux guest additions. When it's done, restart the computer by entering reboot and hitting Enter.

Finally, you can boot into SteamOS. When the screen where you earlier selected recovery mode appears, choose the top option to not start SteamOS in recovery mode. This will, at last, bring you to the SteamOS desktop. It will try to connect to the internet to update Steam--if it fails, try going into the Network Settings box of your virtual machine and changing the network adapter from Bridged to NAT or vice versa.

When you successfully connect to the internet, Steam will download an update. As of publication, that update will restart your system and, essentially, reinstall the operating system all over again. Allow it to complete the automated process, and when you finally get a chance to make a decision at the very end, choose to reboot the computer.

Things finally seem to be looking up, as a brand new SteamOS splash screen loads. Unfortunately, your joy will be short-lived, as the system will now dump you on an empty black screen. To fix this problem, hit ctrl + alt + f2 to open a command prompt. You'll be asked for a login name--enter "desktop."

Next, enter the command sudo dpkg-reconfigure lightdm and hit Enter. Select gdm3 when you're given a choice. Finally, type sudo reboot and hit enter to restart.

This time, you'll have the option to log in to SteamOS. There are two options available for login--choose the top one labelled "Steam OS Desktop." You're now finally back at the SteamOS desktop, but you may notice that if you try and run Steam itself, it won't open.

To fix this final problem, just hit alt + f2, and in the dialogue box that opens up enter gnome-terminal. This will open a terminal, into which you can type the magic word steam and press Enter. This should finally, actually open Steam. Accept the EULA, download any updates, and login with your Steam account.

Finally, after much finagling, you're running Steam in SteamOS! To get the intended living room PC feeling, you can click on the Big Picture Mode icon in the upper right-hand corner to launch a version of Steam optimized for playing from the couch--the true incarnation of the much-balleyhooed SteamOS. To see your Linux-compatible games, which will work on SteamOS, open your games library in, then click the View all games button. In the library screen that appears, simply select the "Linux" option from the drop-down menu--one you won't see in Steam for Windows--to filter out the playable titles.  

SteamOS will probably be a bit laggy in the virtual machine, but you'll be able to get a solid feel for what Valve's gaming-centric operating system is all about.