!
error HP

Error Code Red LED flashes 5 times

Pre-video memory error — incorrect memory configuration or faulty DIMM.

? What Causes This

Incorrect memory configuration or faulty memory module.

How to Fix It

  1. Run Setup (F10) and check DIMMs for proper seating, type, and compatibility with HP systems.
  2. Remove DIMMs singularly and reinsert to identify the faulty one.

Source: page 3 of the official manual

From the manual

Manual page 3 — HP error Red LED flashes 5 times

This error code appears in:

HP Compaq Pro 6300 SF Desktop