Question Need help troubleshooting PC, power issues

[SteelBlood]

I've built and repaired a few PCs myself but this is a weird problem to me I've never encountered before.

This issue started probably 2 months ago, my PC started making noises like it was going into overdrive. It sounded like it was building up power and about to explode. The noise would happen 1-3 times a day (and I'm on like all day). It was inconsistent, it would even happen if I was doing nothing, like having nothing open and just sitting on the desktop. It would stop after a few minutes. I of course looked into this, monitored my CPU temperature, blew off and looked at the fans, nothing seemed out of order. It didn't feel like it was running slower or anything either.

Then one day it wouldn't turn on. Even this bit is inconsistent. At first, it turned on but no display. So I turned it off and tried turning it on again but then it wouldn't even power up. Lights and fans would turn on for a second and then power back down. And then it would keep trying to turn itself on, without me touching anything. It would light up for a second, turn off, wait a few seconds, light up again, turn off, repeat.

I took it apart, tested with another CMOS battery and power supply from another gaming computer I have (that one isn't working either likely due to bad RAM slot on motherboard) and got the same results, so I put the original components back in. I took off the heat sink, inspected the CPU, and reapplied the thermal paste. I discharged the electricity by holding down the power button while the PC was unplugged. And voila! It worked!

Until I shut it down again. Then same exact issue. Its been a few days since then, and it hasn't wanted to turn on again, until today. No display at first, I tried again, and then it worked. I have a hardware monitor program up, and see no excessive power drain, temperatures, or memory usage. The computer is really only 3 or 4 years old.

As you can see, this problem is difficult for me to troubleshoot because it is highly inconsistent. I'm not going to turn it off since I highly doubt I could turn it back on. Any help would be greatly appreciated.

Specs:
Intel i5-7600k
MSI Z270 Gaming Pro Carbon motherboard
Nvidia GeForce GTX 1050ti GPU
16GB RAM
700w PSU

 

[BogdanH]

..my PC started making noises like it was going into overdrive...

where from came the noise, from PSU? What brand is PSU? Yes, you tried with another one (also old I assume)... but symptoms kinda point to PSU...

 

[SteelBlood]

Sorry for the slow reply, had to wait till it made the noise again. PSU brand is Kentek, and I can't exactly pinpoint the noise but it sounds like either PSU or GPU.

 

[BogdanH]

Your CPU has built-in graphic processor... did you try to remove nVidia card and connect monitor to port on motherboard (instead on graphic card)? That could help to pinpoint where the problem is.

 

[SteelBlood]

Thanks for the reply. I have not tried that, but since I am not sure my PC would turn back on after I powered it down to remove the GPU, I am not sure I can try that. You are right in that it would help me pinpoint the sound (and likely, therefore the issue). If I was lucky enough the PC turned on without the GPU, and still made the sound, I'd know it was the PSU. On the other hand, if there is no sound, because it is inconsistent, I wouldn't be able to tell anything. For example, I haven't heard the sound for the past few days at all, but today I've heard it 3 times.