Help! Power supply failure or some other causes of recurrent system lockup?

[to1337ca]

I need some urgent help to troubleshooting my system that is randomly locking up and refusing to boot.

For the past days, my system would suddenly lock up when even idle. Sometimes, but not always, the video output would also disappear. After doing a hard reset, it would work for various periods of time before locking up again. It NEVER, however, auto rebooted. On more than one occasions, after the system was shut down and powered on again, it would not initiate POST even though the hard drive lights, power lights, optical drive lights, and system fans are all on.

At first, I thought there was a system overheating issue, as I previously had a CPU fan failure. I put in a new CPU fan, but the system persisted.

By chance, while observing the PC Health stats from BIOS, I noticed the following:

Vcore 1.252V
DDR18V 1.888V
+3.3V 2.672V (this number varies to 2.760V to up to ~2.9V)
+12V 11.731V

The power supply is a Seasonic 550W but is about 8 years old. I now thought that the cause was a failing power supply. However, when I brought the computer to a local store and showed the technician the reading, the technician insisted that the low +3.3V readings were not sufficient to explain the problem and refused to change the power supply even as a test.

I am unsure what to do. I am not tech savvy. But from what I read online about power supply problems, I think I am correct and the technician is not. I appreciate it if anyone can shred light on this problem.

Other info that may or may not be relevant:

1) My system uses two silent Gigabyte GT8800 old video cards that are fanless, so GPU fan issue does not exist.
2) The motherboard is a Gigabyte GA-X38-DQ6 motherboard.
3) There were no other issues I detected (no USB power loss, no beep from the motherboard during POST).
4) All temperatures including CPU, GPU, were all OK when I was able to monitor them (both in Windows and in BIOS).

PLEASE HELP!!!

[btdog]

Troubleshooting is a pain. Troubleshooting an 8 year-old system is an even greater pain. After about 5 years, most components are susceptible to failure, which means any part could be the culprit, or worse yet, two or more components have failed.

Still, here are my thoughts:

I agree with you, the PSU is typically the most common part to fail and cause symptoms like you're seeing. I don't know why the technician wouldn't swap out PSUs, even if it was for giggles. To test your theory, you'll have to get your hands on a known good PSU. Good news, you can usually find a good quality PSU (Corsair comes to mind) for about $60-70.

After the PSU, in order, I would suspect the mobo, then RAM, then GPU.

I would also remove one of the GPUs. You should remove any non-essential parts to narrow the focus and help with identification of the failed part. CPU, mobo, PSU, RAM, GPU, keyboard, mouse and C: drive are all you need.

You say you're not tech savvy but perhaps a friend of yours who is would be willing to help.

Hope this helps.

[to1337ca]

Thank you, btdog, for your advice. I will follow your recommendations to try them out.

Troubleshooting is a pain. Troubleshooting an 8 year-old system is an even greater pain. After about 5 years, most components are susceptible to failure, which means any part could be the culprit, or worse yet, two or more components have failed.

Still, here are my thoughts:

I agree with you, the PSU is typically the most common part to fail and cause symptoms like you're seeing. I don't know why the technician wouldn't swap out PSUs, even if it was for giggles. To test your theory, you'll have to get your hands on a known good PSU. Good news, you can usually find a good quality PSU (Corsair comes to mind) for about $60-70.

After the PSU, in order, I would suspect the mobo, then RAM, then GPU.

I would also remove one of the GPUs. You should remove any non-essential parts to narrow the focus and help with identification of the failed part. CPU, mobo, PSU, RAM, GPU, keyboard, mouse and C: drive are all you need.

You say you're not tech savvy but perhaps a friend of yours who is would be willing to help.

Hope this helps.