Google is revamping its Chrome OS platform with a new desktop environment and window management system. We took a close look at the user interface improvements earlier this week in a detailed hands-on report. In our review, we explained how advanced users can install the experimental new interface on a Chromebook by enabling the developer update channel.

Of course, that only works if you have a Chromebook. After we published our review, we heard from many readers who wanted to test the latest experimental version of Chrome OS on conventional hardware. In this tutorial, we will explain how to install a third-party build of Google’s operating system in a virtualized environment or on a bootable thumb drive.

Chrome OS is a Linux-based operating system that largely consists of open source software. Independent developers can download the source code from a public repository and compile their own builds of the platform. Google uses the name Chromium OS to distinguish the underlying open source project from the commercial version of the operating system that is shipped by hardware manufacturers.

A third-party build that is based on the code from the open source software repositories is technically called Chromium OS, and is branded accordingly. That’s what we are going to be working with in this tutorial. When you get it up and running, you will notice that the browser icon is blue instead of the usual red, green, and yellow.

Google provides detailed instructions that explain how to download the source code, compile all of the components, and generate a bootable system image. The process is a bit involved, however, and isn’t really intended for enthusiasts who just want to try the software. Fortunately, somebody else has already done all the work.

Liam McLoughlin, who is known as Hexxeh on the Internet, routinely generates up-to-date builds of Chromium OS and publishes them on his website for people to download. He offers two separate flavors of the operating system: vanilla and lime. The vanilla builds are more closely aligned with upstream whereas the lime builds include broader hardware support and additional components, such as a Java plugin.

McLoughlin generates new builds every day using the very latest code from the Chromium OS project. That means his recent builds include the Aura-based user interface and other new features that we looked at in our review. In addition to a standard disk image that is suitable for writing to a USB thumb drive, he also supplies a VirtualBox disk image that can be used to easily set up a virtualized Chromium OS environment.

Before we begin, it’s worth noting that running Chromium OS on a regular computer is not the same as running Chrome OS on a Chromebook. There are some distinctive hardware features in Chromebooks that you generally won’t find in regular netbooks and laptops. One key difference is that Chromebooks have a verified boot mechanism that checks at startup to make sure the operating system hasn’t been compromised.

That feature requires specialized hardware and a signed kernel that is supplied by a hardware manufacturer. It’s obviously not a feature that you are going to get when you run Chromium OS on a regular netbook. It’s also worth noting that these Chromium OS builds aren’t as tightly locked down as the standard Chrome OS. You get a full shell and have broader filesystem access.

Testing Hexxeh’s Chromium OS build

The process of obtaining a Chromium OS disk image and writing it to a USB thumb drive is different for each operating system. Hexxeh supplies a utility for Mac OS X that largely automates the entire process. The tool will download the Chromium OS build specified by the user and then write it to a USB thumb drive.

A similar tool is currently being developed for Windows, but isn’t available yet. Windows users will have to download a disk image from Hexxeh’s website and then use a third-party tool to write it to a USB thumb drive. Hexxeh recommends using Image Writer for Windows, which has a pretty self-explanatory user interface.

Linux users will have to use the dd command at the command line to write the disk image to a USB thumb drive. For reasons that aren’t entirely clear to me, the user-friendly USB disk creator tool that comes bundled with Ubuntu seems to consistently fail with the Chromium OS disk image. The dd command, which is the method that Hexxeh recommends, works perfectly. Please note that dd is unforgiving and can do nasty things to your hard drive if you feed it the wrong parameters.

To download the disk image manually, which you will need to do on Windows or Linux, visit Hexxeh’s website and click the USB thumb drive icon next to the latest build. I chose to use the vanilla flavor, which ended up working pretty well on my hardware. The disk image is compressed in a zip archive, with a total download size of 256MB. Hexxeh recommends installing it on a USB storage device that is at least 4GB.

After you write the image to a USB thumb drive, you can get a complete Chromium OS experience by booting from the device. The vast majority of modern PCs natively support USB booting, but you may need to jump through some hoops to get it to work. On most computers, it’s a simple matter of activating a boot device selection menu during startup. On some computers, you might need to go into the bios and manually configure the boot device order.

I tested Hexxeh’s Chromium OS builds on my HP netbook. When the HP logo appears during startup, I have to press the escape key to get to the boot menu and then F9 to get to the boot device selection list. The list lets me choose between booting from the built-in hard drive or the USB thumb drive.

Booting from a USB drive is obviously a lot slower than booting from an internal SSD, so it’s going to take a bit longer than it would on a Chromebook. The process is still pretty fast, however. You will see the Chromium OS logo on the screen for a few moments while the system is booting. When it finishes, you will be presented with the platform’s initial setup wizard. It will walk you through the steps of setting up your WiFi network and user account.

You only have to go through this setup process the first time that you boot the operating system from the USB thumb drive. On subsequent startups, you will instead see the login screen. After you get past the setup or login screen, you will see the Chromium OS desktop in all its Aura-enabled glory.

Hexxeh’s vanilla build worked mostly as expected on my HP netbook, but I encountered several minor hardware problems. The Synaptics clickpad on the netbook proved especially problematic and couldn’t handle click-and-drag operations reliably. I also encountered some difficulty getting the system to resume from a suspended state during my tests.

I had no trouble with WiFi, however, which worked perfectly out of the box. You might see different results, depending on your hardware. If you encounter serious hardware problems, you might want to check and see if your system is better supported by the Lime build.

Virtualization

As noted above, Hexxeh provides VirtualBox disk images alongside the USB images. The VirtualBox images are useful if you want to test Chromium OS in a virtualized environment instead of running it natively on hardware. The image is supplied in a VDI file, which is VirtualBox’s standard virtual disk format.

When you create a new virtual machine in VirtualBox and reach the step where it prompts you to specify a virtual hard disk, click the “Use existing hard disk” option. Next, click the folder icon to the right of the disk selection list. You will see a file selection dialog, which you can use to select the VDI file.

The vanilla Chromium OS build works well in VirtualBox, though you won’t be able to take advantage of the VirtualBox features that require guest additions. I had some minor issues with cursor control and had to select the option to disable mouse integration from the Machine menu.

Conclusion

Hexxeh’s builds are currently aimed at supporting conventional x86 hardware, but he’s also exploring other possibilities. In a recent Twitter post, he demonstrated an ARM build of Chromium OS booting on the $35 Raspberry Pi Linux computer. It’s possible that the enthusiast community will bring the platform to a variety of other hardware devices and form factors.

Using the instructions in this article, you should be able to get a taste of what Google is going to offer with the next generation of Chrome OS, including the much-improved user interface. Although running a third-party build on conventional hardware probably isn’t practical for day-to-day use, it’s an easy way to explore the capabilities of Google’s operating system without having to purchase a Chromebook.