What is POST-CODE-55?
POST Critical Error (Code 55 - Memory) (POST-CODE-55) is a critical-severity fault affecting the motherboard. The board failed to initialize RAM during boot. The usual suspects are dead battery CR2032, short circuit on the motherboard, aborted BIOS update process and age of capacitors. Follow the steps below to fix it.
Common Causes
- Dead battery CR2032
- Short circuit on the motherboard
- Aborted BIOS update process
- Age of capacitors
Step-by-Step Fix Guide
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1
Replace the CMOS battery on the motherboard
Replace the CMOS battery on the motherboard resolves the majority of POST-CODE-55 cases on its own, making it the logical starting point.
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2
Use the USB BIOS Flashback function (if the board has a button)
A second occurrence often means a less common mobo instability cause is at play, which later steps address.
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3
Check the rear I/O panel for a short
This step, "Check the rear I/O panel for a short", specifically rules out short circuit on the motherboard.
Commands & Diagnostics
systeminfo | findstr /C:"BIOS Version"
Frequently Asked Questions
POST-CODE-55 is most often triggered by dead battery CR2032. Other reports point to short circuit on the motherboard, aborted BIOS update process and age of capacitors as contributing factors.
The fastest fix is "Replace the CMOS battery on the motherboard". Only move on to the later steps if POST-CODE-55 keeps coming back.
Treat POST-CODE-55 as urgent — it's flagged critical severity, meaning repeated occurrences risk data loss or hardware damage.
Usually. POST-CODE-55 is fixable with the steps above; a full Windows reinstall is rarely necessary unless everything else has failed.
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