We have a fault with the following configuration, which appears to be power supply or management related.
The system runs Windows 7, 64 bit Pro. It has been in normal operation for 6 months: this is a new intermittent fault of increasing frequency.
The fault initially manifested as apparent failure of KB and mouse. When the system was power cycled to restart, it failed to boot.
After a period (around 30 minutes) the system booted, apparently normally.
The fault has now hardened, and shows either the above or sudden power outage after a few minutes’ operation. When power fails, there is an audible click.
When the system fails to boot (all cases) it apparently fails to complete the POST operation (there is not beep code). The Green Motherboard PWR LED is visible and on.
When the system was last run, I used the Intel Desktop Utilities (V3.2.0): these showed all supplies, fans and monitored temperatures to be in their normal operating ranges. No change was displayed up to the point of sudden failure, when the power failed.
What is not clear is whether the Motherboard has detected an invalid condition and forced power supply shutdown, or whether the power supply’s
own monitoring has caused it to shut. It is clear that these system components interact: the PWR LED may indicate which the “guilty” party is, but that’s not clear from the documentation.
Can anyone recommend further tests which would indicate which system component is the most likely source of the problem?