The Fujitsu Esprimo Q920 is not fundamentally incompatible with ZimaOS: Fujitsu documents UEFI firmware on the Q920, and current ZimaOS explicitly requires UEFI boot with Secure Boot disabled. If the SSD boots in another computer but the Q920 says “Reboot and select proper boot device,” focus on firmware boot mode and how the disk was installed.
The source thread points to a bootloader/firmware mismatch, not a storage-image failure. ZimaOS loaded from the same SSD in a laptop, which is strong evidence that the installation itself was readable.
Confirm the Q920 Is Using UEFI
Fujitsu's Q920 data sheet lists AMI Aptio firmware with Unified Extensible Firmware Interface support. Enter firmware setup and select UEFI boot rather than legacy/CSM-only mode.
The current ZimaOS installation guide requires UEFI and says Secure Boot should be disabled.
Do Not Install the SSD in Another PC as the First Choice
Installing to the target Q920 is safer because the installer can create the boot entry in the firmware environment you will actually use. Cross-installing a drive can leave the target machine without the expected UEFI boot entry.
Recreate the Installer on USB
Flash the current ZimaOS image with Balena Etcher, boot the Q920 from that USB in UEFI mode, choose the internal SSD as the target, and let the installer finish completely.
Disable Secure Boot
If Secure Boot is enabled, ZimaOS may appear in a boot list yet fail to start as expected. Turn Secure Boot off for the installation and first boot.
Check the SSD and Boot Entry
After installation, remove the USB and look for the ZimaOS/internal-drive UEFI entry. If the SSD is listed only under legacy boot devices, the machine may be attempting the wrong boot path.
Check SATA Mode Only if the SSD Is Missing
If the installer sees the SSD, SATA mode is probably not the main problem. If it does not, record whether the Q920 uses AHCI or another controller mode before changing firmware settings.
Update Old Q920 Firmware if Necessary
The Q920 is older business hardware. A firmware update can improve UEFI boot behavior, but use Fujitsu's official update package and keep power stable during the update.
The installation troubleshooting guide provides a broader checklist.
Check the EFI System Partition After Installation
If the Q920 still refuses to boot, inspect the installed SSD from another Linux system and confirm it contains an EFI System Partition. A disk that only has a legacy bootloader will not satisfy the current UEFI-only ZimaOS path.
Use the One-Time Boot Menu for Testing
Before changing permanent firmware order, use the Q920 one-time boot menu and explicitly choose the UEFI entry for the internal SSD. If that works, move the same entry to the top of the normal boot order.
Keep the Installer USB Until the Internal Boot Is Proven
Do not erase the installer immediately after installation. Keep it available until the Q920 has cold-booted successfully from the internal SSD at least once.
FAQ
Does the Fujitsu Q920 support UEFI?
Yes. Fujitsu's hardware documentation lists UEFI support.
Why does the SSD boot in a laptop but not the Q920?
The target Q920 may be using legacy boot, Secure Boot, or lack the correct UEFI boot entry.
Should I use CSM/Legacy mode?
No. Current ZimaOS documentation requires UEFI boot.
Is the Intel I217LM Ethernet likely to work?
It is a common Intel Gigabit controller, but boot success should be solved before diagnosing network compatibility.
