Desktop POST Hardware System: hardware compatibility mismatch. A part fits but its electrical specification or firmware support differs.

The distinguishing clue

The system is stable with the original part but not the replacement.

Checks before an assessment

Record the exact POST light, beep or code and the motherboard model. Check the monitor input externally; do not treat a diagnostic light as proof that a named part is defective.

Stop point: Repeated part swapping with power connected can damage components.

Workshop confirmation and repair

Device-level check: Record codes and test minimum known-good hardware in a fixed order.

Targeted check: Compare supported revisions, capacity, timings and power requirements. If confirmed: Install a supported component and restore approved configuration.

Repair boundary: Repair the confirmed memory, graphics, processor, firmware or board stage.

Related cause to rule out

When diagnostic progress stops before the operating system loads, also consider Desktop Stuck at POST: Use Diagnostic Codes Without Guessing the Failed Part before choosing a repair.

Checks after the work

After repair or replacement, check cold boot, diagnostic indicators, full detection, restart and sleep.

For an AEPC repair assessment in East Auckland, provide the exact model and observed clue. Call 027 908 8880 before visiting the Burswood workshop.