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error HP

Error Code Red LED flashes five times, once every second

Pre-video memory error: Reseating or replacing memory modules.

? What Causes This

Problem with the memory modules

How to Fix It

  1. Reseat memory modules.
  2. Replace one module at a time to isolate faulty module
  3. If issues persist, replace third-party memory with HP memory and test again.
  4. If no success, substitute system board.

Source: page 39 of the official manual

From the manual

Manual page 39 — HP error Red LED flashes five times, once every second

This error code appears in:

HP T630 Thin Client