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  • FAQ
  • Firmware
    • Finding System Info
    • Supported Devices
    • Known Issues
    • Developer Mode
      • Recovery Mode
    • Disabling Write Protect
      • Using a SuzyQable
      • Unplugging the Battery
    • Types of Firmware
      • RW_LEGACY
      • (UEFI) Full ROM
    • Flashing Firmware
    • Updating Firmware
    • Compiling Custom Firmware
    • Flashing Manually
  • Installing an OS
    • Known Issues
    • Installing Windows
    • Installing Linux
      • Partitioning Instructions for Dual Booting
      • Notes for non-standard distros
    • Installing MacOS
      • Custom macOS firmware
      • Fixing Hibernation
    • Post Install
    • Using ectool
  • Debugging
    • Reporting Bugs
  • Unbricking
    • Unbricking with a ch341a USB Programmer
    • Unbricking with a Suzy-Q Cable
    • Unbricking with a Flipper Zero
  • Reverting to chromeOS
    • Flashing Stock Firmware
    • Making a Recovery USB
    • Booting the Recovery USB
  • Contributing

Types of Firmware

RW_LEGACY

  • Updates/replaces the stock RW_LEGACY payload (SeaBIOS or edk2) included on many older models; supplements the ChromeOS / secure boot payload (depthcharge)
  • Leaves all stock functionality intact, including the Developer Mode boot screen and Recovery Mode functionality
  • Allows device to dual-boot linux alongside ChromeOS
  • Does not require disabling write-protect
  • Carries zero risk of bricking the device
  • On many models, includes bugfixes and enables additional functionality

Warning

Do not run Windows on RW_LEGACY. The RW_LEGACY firmware is for users who want to dual-boot ChromeOS + Linux, or users who want to run Linux without having to open the device/disable the firmware write-protect (and are OK with the accompanying limitations).

(UEFI) Full ROM

  • A complete firmware image which includes updated/customized versions of the hardware init component (coreboot) and UEFI boot payload (edk2)
  • Removes the developer mode boot ("OS verification is OFF") screen
  • Completely removes the ability to run ChromeOS (and ChromeOS Recovery Mode), creating a small risk of bricking your device
  • Offers the best support for booting all OSes besides ChromeOS
  • Adds full hardware support for virtualization (vmx / VT-x)
  • Fixes many bugs and/or idiosyncrasies associated with the stock firmware
  • UEFI firmware contains updated EC firmware as well, which brings additional fixes on most Chromebooks (mainly keyboard related)
  • Requires installation of a UEFI-compatible OS after flashing
  • Essentially turns your ChromeOS device into a "regular" PC / laptop

Tips

The (UEFI) Full ROM firmware is the best option for all users who no longer need/want to run ChromeOS (ie, want to run Linux/Windows/macOS exclusively), and who do not mind disabling write-protection on their device.

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Disabling Write Protect
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