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error HP
Error Code Red LED blinks 5 times every second followed by a 2 seconds pause
Pre-video memory error occurred.
? What Causes This
Incorrect or faulty memory installation.
✓ How to Fix It
1. Verify that RAM modules are properly installed and seated in their sockets. If issue persists, isolate and replace any faulty DIMMs.
Source: page 2 of the official manual
From the manual
This error code appears in:
HP Compaq Elite 8300 Small Form Factor PC