Guide To Flash SeaBIOS, Custom Firmware, On Chromebook

I bought Dell Chromebook 11 about 1.5 years ago. Being a university student (at that time), the Chromebook served me well. It had 4 GB RAM and i5 Intel processor, which were way beyond what Chrome OS required. Fast forward to year 2017, its battery is dead and I have been searching for a way to convert it into a more useful machine. Now, Chrome OS, by its nature, isn’t as useful as you would expect it to be. This is even more true for a power user.

Indeed there are hacky ways to run Ubuntu atop Chrome OS using Crouton but that’s not a real deal. It works really well but I don’t want the dependency on Chrome OS. The other alternative is to completely replace Chrome OS with the operating system of your choice. Awesome, this is what I want but the problem here is you would have to get your hands messy. And this is precisely the purpose of this article. To help you through the process of preparing your Chromebook for flashing a custom firmware i.e. SeaBIOS and making sure it is ready for installation of any other OS. Alright then, let’s get started!

Check Compatibility

Before attempting to flash the custom firmware, it is very important to check if your Chromebook is supported by John Lewis’s ROM (SeaBIOS). Head over to the ROM download page located here and look for your Chromebook under “Supported Models Matrix” table (FULL ROM column). If you can see your Chromebook listed under specified column then you should be okay to proceed. In my case, the Dell Chromebook 11 (WOLF) is present.

Note – This guide might also work for the Chromebook listed under “RW_LEGACY” or “BOOT_STUB”. But I haven’t tested any other Chromebook except for Dell Chromebook 11 (Intel i5 processor).

Remove Write Protection

This is the messy part and you’ll be needing screw driver. Chromebooks have a write protection mechanism put in place to avoid flashing its ROM. Write-protect can be disabled jumper/removing a screw but since this jumper/screw is located on the main board, you need to open up the Chromebook.

Although ripping apart my Dell Chromebook 11 wasn’t difficult (needed to open a dozen on screws) but the difficulty level can vary for your Chromebook. The best way to understand where the jumper/screw is located and how to disable it, visit the Developer Information for Chrome OS Devices web page. Click on your Chromebook model and refer the section “What’s Inside?” section to see relevant information.

Once you have the necessary information, the next step is to disable jumper/unscrew the screw. Re-assemble the Chromebook and power it on to ensure everything is working. Note that the toughest part is over!

Enable Developer Mode

Now that write-protection is disabled, we are free to overwrite the ROM. For doing so, first step is the enable developer mode so as to be able to have necessary permissions required for flashing custom firmware.

Instead of repeating the entire process of enabling developer mode, I will refer you to the guide written by How-To Geek – How to Enable Developer Mode on Your Chromebook. Come back to this page once you have enabled the Developer Mode successfully.

Flashing SeaBIOS

Open the Crosh shell. To open the Crosh shell, press Ctrl+Alt+T anywhere in Chrome OS. The Crosh shell will open in a browser tab. Before moving on, make sure you are NOT in root shell and that the command prompt looks something like the following image.

The last step is to run the following command.

cd; rm -f flash_chromebook_rom.sh; curl -O https://johnlewis.ie/flash_chromebook_rom.sh; sudo -E bash flash_chromebook_rom.sh

The flash script is taken directly from John Lewis’s website. If need be, you can verify the correctness of the script visit the website and look towards the end of the article (just before comments section).

Once the firmware is flashed, you will notice a BIOS similar to one you’ve been seeing on traditional Windows desktops/laptops. Now on-wards, install Ubuntu or any other linux distro as you normally do.