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Installing Aurora OS on Chromebook

· 5 min read
Bob Devitt
Bob Devitt
Author

I found it quite straightforward to wipe my Lenovo Flex 5i Chromebook purchased from Costco in 2023 and install Universal Blue's Aurora OS instead. Here's a loose guide to do so, complete with references!

Introduction​

danger

This guide makes unsupported changes to your device that will in many cases void your warranty. This guide, MrChromebox firmware and utilities, and Chrultrabook utilities are provided as-is, without any guarantee. Any and all changes are made at your own risk!

I purchased my Lenovo Flex 5i Chromebook from Costco in 2023... arguably not that old. It was still functional. Chrome OS worked fine... as much as a proprietary system can.

But we all know why we're here, let's nuke this Google system and install a open source modern OS: Universal Blue's Aurora OS - based on Fedora Kinoite. https://getaurora.dev/en/

This guide is for "UEFI Full Rom Firmware" replacement. It completely wipes out the original Chromebook firmware and essentially turns the Chromebook into a "regular" PC using UEFI firmware. It is NOT for dual boot use cases if you still want to utilize the original ChromeOS.

There are two main complimentary resources:

If you do not have a Lenovo Flex 5i Chromebook, I will refer you to above. The rest of this guide will not quite apply.

Use the above resources as your primary. This guide is only meant to be complimentary.

Preparing the Lenovo Flex 5i Chromebook for firmware flashing​

  1. First things first: backup anything important. All data will be lost.
  2. Boot into Recovery Mode: ESC + Refresh (arrow icon) + Power. The Refresh button is two buttons down from the ESC. The Power button is on the right side.
  3. Enable Developer Mode: Press [CTRL+D] and then [ENTER] to Enable Developer Mode.
  4. Disable the CR50 hardware firmware write protection by disconnecting the battery: Shutoff the Chromebook and open the back with a torx T4 bit used to loosen the 9 exposed torx screws around the edge.
    (There are no hidden ones under the rubber footings). Use a plastic "pick" to gently pry and pop open the case. Disconnect the lithium battery connection.

Flash the Chromebook with the MrChromebox utility script​

  1. Boot the Chromebook using the 45W power adapter (regular USB-C chargers will not work - I tried, it will send it into a boot loop).
  2. Once the UI is up and it begins asking you to setup. Setup wifi/internet first, then press [CTRL+ALT+F2] to enter the shell. F2 also corresponds to the "back" arrow on the Flex 5i Chromebook.
  3. Login using the name chronos which does not require a password.
  4. Download and run the Firmware Utility Script: cd; curl -LOf https://mrchromebox.tech/firmware-util.sh && sudo bash firmware-util.sh. If typing this in manually, make sure it is the "Oh" option, not the "Zero" option in -LOf. Also double check the link is still correct in the original reference. The utility script is also available on github: https://raw.githubusercontent.com/MrChromebox/scripts/refs/heads/main/firmware-util.sh
  5. This script will guide you through firmware flashing. If ran the first time, it may disable software firmware write protection and ask to reboot - requiring you to download and run the script again.
  6. Select option 2 from the main menu: "Install/Update UEFI (Full ROM) Firmware". It will give you an opportunity to backup the original ChromeOS firmware to a USB stick, which I recommend.
  7. It may take a number of minutes to complete the flash. Do not poweroff even if the screen appears frozen. My Lenovo Flex 5i completed in less than 10 minutes.
  8. Important: When the flash is complete, select the Poweroff option in the utility script. Do not reboot immediately.
  9. Reconnect the battery connection and boot up the Chromebook

Install Aurora OS​

  1. Use the Aurora OS Live USB created with Fedora Media Writer to boot and install the OS. When installing, select "use entire disk" to rid the Chromebook of its original ChromeOS partitions.
  • Chrultrabook says that there will be likely audio issues initially, but that was not my experience. Aurora actually connected to my Denon system by default, which was very confusing to hear audio coming from the other room. Once the default audio device was set to the internal audio, it worked perfectly.
  • Chrultrabook also says there may be USB-C issues with AlderLake CPUs such as the Flex 5i i3-1215u. This was not the case for me on Aurora OS, USB C worked fine out of the box.
  • If you have issues on your Chromebook after a linux install, be sure to check Chrultrabook for post install fixes.

Final Thoughts​

This was a very painless and easy process for the Lenovo Flex 5i. I'm excited to keep using this hardware for years to come for remote development when traveling.