Is my HP computer still working after it has been turned off multiple times due to power outages?
Is my HP computer still working after it has been turned off multiple times due to power outages?
I own an HP ProDesk 400 G5 and experienced some power interruptions recently. My machine was running during the first two outages. After that, I powered it off for a while, then restarted it later when the lights seemed stable. Once again, the power went out. I left it unplugged for the rest of the day, but it stopped working entirely. I always keep my PC connected to a filter line, which is still functioning properly with my monitor.
I took it to a repair shop, but they mentioned they can't test these kinds of power supplies or motherboards. So I was going to replace them myself. Living in a small city, there aren’t many repair options nearby.
When trying to turn it on, the light comes on but then fades away instantly—similar to the speaker light connected directly to the PC. There’s no fan noise or any movement inside the case. When I accidentally touched the back of the PC, I felt a small shock, though I’m not sure if that matters.
I found that you can test a power supply with a paper clip, but my unit has a 24-pin cable instead of a standard one. It has two sets of four-pin cables and another set with seven slots, but only five cables are connected. Is there a way to check this power supply before replacing it? Or should I try other methods to identify the issue?
I just attempted it following your advice, but it didn't function properly. I also connected the power supply to check with a multimeter, and it was operating correctly.
No matter how you attempt to assist with the computer problem, avoid touching the outside of the PC. At least refrain from using the outlet that the PC was connected to until it has been checked and confirmed as properly wired and safe. When troubleshooting unusual non-functioning systems, place them in a backup power supply. If that doesn’t work, try booting the system with just one memory stick, testing each stick individually to identify the faulty one. If booting still fails, proceed without any hardware—no hard drive connected. It’s a gray area whether you should or shouldn’t connect front panel wires; some OEM models may react negatively if they detect missing connections. Ensure your mouse and keyboard are attached to the motherboard, not the front panel USB ports. Do you have a different monitor/mouse and keyboard for testing?
My idea is that repeated power surges could have caused components such as a diode, resistor, capacitor, or solder to fail, possibly melting on the board. If you can, check the motherboard carefully for any signs of damage like melted areas or black spots.