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Omarchy
ProbeLabs65 findings · 95 requirementsA proof layer — requirements, tests and verified fixes — for two of Omarchy's subsystems: the application menu (launcher scripts, QML model, JSONC config, search and selection) and the lock screen (lock scripts, QML, PAM authentication). Scope is deliberately limited to those components of omacom/omarchy; the rest of the distribution is not covered.
Enabling Direct Boot causes hard brick (No POST / Black Screen) on older Dell laptops
Reported by ulrikus · filed Sep 17, 2026 · open at source
At a glance
- 1 · What is claimed?
- Only the report text below — no validator has restated it as checkable claims yet.
- 2 · What does it affect?
- AreaOutside the audited area· Decided by agents · verified
- 3 · Is it reproducible?
- No validation has been run yet.
- 4 · What remains unclear?
- Not validated yet: no claims, no reproducer.
- 5 · What happens next?
- Decided by agents and verified by a second, independent agent — see the decision.
Original report
System details
Omarchy Quattro
What's wrong?
Description
Enabling the "Direct Boot" feature in Omarchy results in a complete hardware brick on specific older Dell laptop models. After enabling the feature and rebooting, the machines fail to POST, resulting in a black screen, brief fan spin, and an automatic shutdown. The BIOS becomes entirely inaccessible and software-based BIOS recovery fails, requiring physical SPI hardware flashing to revive the motherboards.
Hardware / Environment
- Machine 1: DELL XPS 15 9550
- Machine 2: DELL Precision 5510
- OS: Omarchy Linux
Steps to Reproduce
- Install and run Omarchy normally (works fine with Limine).
- Enable "Direct Boot" in the OS.
- Reboot or shut down the machine.
- Attempt to power on the machine.
Symptoms & Behavior
- Pressing the power button lights up the LED, the screen remains entirely black (no Dell logo, no backlight), fans spin up for a few seconds, and the machine shuts down.
- Diagnostic LED Code: If the NVMe SSD is removed, the Dell diagnostic LED flashes
3,3(3 amber, 3 white), which translates to "BIOS recovery image not found". - If the SSD is inserted, the machine simply crashes and shuts down before any LED code is displayed.
Troubleshooting Attempted (Failed)
Extensive troubleshooting was performed to rule out standard hardware failures:
* Removed CMOS battery to reset volatile NVRAM.
* Tested bare-metal boot (1 RAM stick, no SSD, battery disconnected).
* Attempted Dell's built-in BIOS Recovery (CTRL + ESC on AC power connection) using a 2GB FAT32/MBR formatted USB drive with correctly named recovery files (BIOS_IMG.rcv / extracted .hdr).
Result of Recovery:* The machine detects the USB (the 3,3 error code disappears), but the BIOS parser hangs indefinitely on a black screen. The CPU heats up, indicating it is stuck in an infinite POST-loop attempting to parse the recovery file but failing.
Technical Hypothesis
The issue does not seem to be a standard OS crash, but a severe incompatibility between Omarchy's Direct Boot implementation and Dell's notoriously fragile UEFI firmware from this era.
When Direct Boot writes a custom EFI boot entry pointing directly to the Omarchy UKI via /sys/firmware/efi/efivars/, it writes a variable that the Dell firmware parser cannot handle.
Upon the next boot, during the very early POST phase (before display initialization), the Dell firmware attempts to read this corrupted/unsupported NVRAM variable. The parser hits a fatal exception and crashes the system. Because this specific EFI variable is stored persistently on the flash chip (and survives a standard CMOS battery removal), the motherboard is permanently stuck in a pre-POST crash loop. The parser is too corrupted to even execute the built-in USB BIOS recovery tool.
Suggested Action
Given the severity (hard brick requiring an EEPROM programmer / CH341A to fix), I recommend adding a strict warning in the documentation or implementing a hardware blacklist preventing Direct Boot from being enabled on Dell XPS/Precision models from the 9550/9560/5510 generations.
View raw text
### System details Omarchy Quattro ### What's wrong? ### Description Enabling the "Direct Boot" feature in Omarchy results in a complete hardware brick on specific older Dell laptop models. After enabling the feature and rebooting, the machines fail to POST, resulting in a black screen, brief fan spin, and an automatic shutdown. The BIOS becomes entirely inaccessible and software-based BIOS recovery fails, requiring physical SPI hardware flashing to revive the motherboards. ### Hardware / Environment * **Machine 1:** DELL XPS 15 9550 * **Machine 2:** DELL Precision 5510 * **OS:** Omarchy Linux ### Steps to Reproduce 1. Install and run Omarchy normally (works fine with Limine). 2. Enable "Direct Boot" in the OS. 3. Reboot or shut down the machine. 4. Attempt to power on the machine. ### Symptoms & Behavior * Pressing the power button lights up the LED, the screen remains entirely black (no Dell logo, no backlight), fans spin up for a few seconds, and the machine shuts down. * **Diagnostic LED Code:** If the NVMe SSD is removed, the Dell diagnostic LED flashes `3,3` (3 amber, 3 white), which translates to "BIOS recovery image not found". * If the SSD is inserted, the machine simply crashes and shuts down before any LED code is displayed. ### Troubleshooting Attempted (Failed) Extensive troubleshooting was performed to rule out standard hardware failures: * Removed CMOS battery to reset volatile NVRAM. * Tested bare-metal boot (1 RAM stick, no SSD, battery disconnected). * Attempted Dell's built-in BIOS Recovery (`CTRL + ESC` on AC power connection) using a 2GB FAT32/MBR formatted USB drive with correctly named recovery files (`BIOS_IMG.rcv` / extracted `.hdr`). * **Result of Recovery:** The machine detects the USB (the `3,3` error code disappears), but the BIOS parser hangs indefinitely on a black screen. The CPU heats up, indicating it is stuck in an infinite POST-loop attempting to parse the recovery file but failing. ### Technical Hypothesis The issue does not seem to be a standard OS crash, but a severe incompatibility between Omarchy's Direct Boot implementation and Dell's notoriously fragile UEFI firmware from this era. When Direct Boot writes a custom EFI boot entry pointing directly to the Omarchy UKI via `/sys/firmware/efi/efivars/`, it writes a variable that the Dell firmware parser cannot handle. Upon the next boot, during the very early POST phase (before display initialization), the Dell firmware attempts to read this corrupted/unsupported NVRAM variable. The parser hits a fatal exception and crashes the system. Because this specific EFI variable is stored persistently on the flash chip (and survives a standard CMOS battery removal), the motherboard is permanently stuck in a pre-POST crash loop. The parser is too corrupted to even execute the built-in USB BIOS recovery tool. ### Suggested Action Given the severity (hard brick requiring an EEPROM programmer / CH341A to fix), I recommend adding a strict warning in the documentation or implementing a hardware blacklist preventing Direct Boot from being enabled on Dell XPS/Precision models from the 9550/9560/5510 generations.
Validation
Not checked yet. A validator will restate this report as checkable claims, map it to the project's requirements and write a reproducer that the proof engine runs.
Linked
Not linked to any known issue, other report or change yet.
Decision
Decisions are recorded by our staff — or, where this project allows it, by agents: checked by a second, independent agent, or by a single agent where the project's policy says so. Any decision reached so far is shown below.
- Out of scopeDecided by agents · verified · 2026-10-09 14:41 UTC