01-04-2018 09:35 PM
System: h8-1150z (AMD, Radeon 6850, USB keyboard&mouse, protected by APC Back-UPS NS 1080)
After a normal spreadsheet & Firefox session, I set the system into Sleep mode (as usual).
When I came back the next day, the system would not resume from sleep. No beeps, no video. Although I didn't take note at the time, the power button LED may have been blue (on) instead of yellow (sleep).
I held the power button to force a power-down, waited a few seconds, then pressed it again to power up. The power button LED lit blue and front bezel LED lit, the power supply LED is on solidly, the fans spun and HDDs spun up. However, the system emitted no beeps and produced no video at either DVI port, and no HDD activity.
I retried several times with no change in outcome.
I looked up the problem on HP Support, and followed the "No Power or No Boot Guided Troubleshooter" but the problem persists. I did not attempt to execute the 'Recover BIOS' step since no BIOS update has occurred recently, and I suspect that the procedure would not work with a USB keyboard.
As a last resort, I plugged the system directly into the wall outlet to bypass the UPS, but no change in behavior.
What can be done to uncover a clue (or two) about the cause of this failure?
01-05-2018 12:17 AM
> What can be done to uncover a clue ?
One thing to try:
Remove the disk-drive from the computer.
Find a working desktop computer with a CD/DVD device.
Disconnect the "power" and "data" cables from the back of the CD/DVD device.
Temporarily connect those cables to the disk-drive, to make it a "secondary" disk-drive.
Boot the computer from the "primary" disk-drive.
See if the computer detects the "secondary" disk-drive at all, and if you can read from the "root" of that file-system.
If not, then that disk-drive has failed.
This is one "clue" -- possibly not helpful.
01-07-2018 05:47 PM
Thanks for the suggestion.
However, I prioritized following the 'no beep' during power-on clue. Other online comments suggested unplugging everything but the processor from the motherboard with the intent of prompting a POST failure and beep codes that could be followed and modified by incrementally replacing connections.
In the minimal configuration, the system still produced no beeps. From this it seems likely to me that something integral to the motherboard has failed.
Alternative interpretations are welcomed.
01-08-2018 01:39 AM
> From this it seems likely to me that something integral to the motherboard has failed.
Remember that the power-supply has to output different voltage-levels to different components, e.g., 4-pin connector to the motherboard near the CPU, 6-pin connector to a high-end PCI-E graphics adapter, 5 volts to the diskette drive, some voltage to the CPU fan, main connector to motherboard, power to SATA devices. A "partial" failure is possible.