Question Sabertooth x79 Rebuilt PC Won’t Start Properly – Output Issues After Running for a Long Time / Turning It Off

[Changali]

About a week ago, I decided to rebuild my old PC, which I had from 2015 to 2020. I had the motherboard, RAM, CPU, and cooler ready, so I just added the rest of the parts. Everything worked great on the first day while I was at my friend's house.

However, when I brought the PC back home and pressed the power button, it made a sound, the RGB lights turned on, and everything was spinning, but there was no output. I checked everything, and it seemed fine. The next day, I took the PC to a repair shop, and they refreshed the BIOS, which somehow made it work.

Back home, the PC started up fine, and I shut it down normally, then turned off the PSU switch. A few minutes later, I tried to start it again, but the same issue came back. I attempted to refresh the BIOS by holding the button for a few seconds—it blinked twice. I plugged everything back in, but it didn't work. I then took the battery out for 10 minutes, and it worked again. The PC ran great, the temperatures were fine, and I tried toggling the PSU switch again, but this time for a short period. The PC booted up normally.

However, after shutting down the PC and toggling the PSU switch, the issue returned. Now, when I click the BIOS reset button, it doesn't even blink, and removing the battery doesn't work either.

I changed the battery, but the PC still did not turn on. I brought it back to the shop. The technician tried changing the RAM slots, booting with a different GPU, and running lower RAM configurations. It worked after he swapped back to the default setup as well. However, as time passed, the PC just turned itself off and produced no output. It worked fine in the shop, but when I brought it home and let it run for a few hours, it just turned itself off again. I tried everything: clearing the RAM with the button, resetting the BIOS, but nothing works.

Could the motherboard be dead? The PSU is new, so I don't think that's the issue. Any ideas would be appreciated. I have the latest BIOS available on the ASUS website. Are there any modded ones that could help?

Specs:

• Motherboard: Sabertooth x79
• CPU: i7 3930k
• RAM: 16GB Corsair 2133
• GPU: RX 580
• PSU: Deepcool 650PF

 

[Lutfij]

Welcome to the forums, newcomer!

The next day, I took the PC to a repair shop, and they refreshed the BIOS, which somehow made it work.
If they reflashed the BIOS, then it's highly possible that the BIOS chip is in need of replacing. You can source the right BIOS chip off of Ebay with the BIOS flashed onto it or you can grab a CH341A BIOS programmaer and reflash the BIOS chip yourself. I've been able to revive a few motherboard's using said toolkit(BIOS programmer).

You might want to inspect the entire motherboard for any blown/bulging/swollen capacitors.

I then took the battery out for 10 minutes, and it worked again. The PC ran great, the temperatures were fine, and I tried toggling the PSU switch again, but this time for a short period. The PC booted up normally.
Apart from a corrupt BIOS, I'm also thinking you might be having a grounding issue, can you relocate to another wall outlet?

Are there any modded ones that could help?
Stick to the factory provided BIOS.

 

[Changali]

Thanks for reply!

I have tried different outlets, and the PC shop workers did as well.

The PC shop worker inspected everything manually and told me the motherboard was visually fine. He advised me to click the "clearing RAM button" if it does not load or refresh the BIOS. It worked when I was there. he restarted it multiple times and fully unplugged it. However, when I did the same stuff at home, after a few hours of using it, all the fans were spinning, but there was no output. If I had done it with a with a small time gap, it would work because when I tried it, it was fine.

Sometimes, removing the BIOS battery worked. other times, it did not. Sometimes, running low-speed RAM worked. other times, it did not, and the same goes for the current RAM. Swapping some parts makes it work, but not for long. its not consistent.

I had the motherboard, CPU, cooler, and RAM in the closet for a long time—could this have damaged them? The funniest part is when it’s booting, it can even pass stress tests and play games, but then it randomly dies or fails after switching the power supply for longer than a few minutes.

What confuses me is why removing the battery once worked but not the second time, and why swapping RAM fixes the issues sometimes. There seems to be no logical connection, so I assume something might be really broken with the motherboard.