Question PC Apparently Dead

[LatinoF]

Last Friday my case fans (connected to the motherboard through a 3 way splitter) stopped working so i started troubleshooting, I started disconnecting the fans from the splitter and after the first fan removed the others powered back on, after a while I smelt burning smell so I immediately turned off the PC and disconnected the splitter from the motherboard and connected it to the PSU with a molex to 3pin fan connector and fully powered the PC, even tried running a game for 30 minutes and everything seemed fine.

I power off the PC and moved it to the main workstation, no sign of life when pressing the power on button so i tried toggling on/off the PSU and removing the power cord a few times and then fully started and worked like noting happened. The next day (Saturday) again the pc powered on correctly and ran fine for 16hours then I power it off to go to sleep, this was the last time it was running because today (Sunday) no sign of life when trying to power it on (no fans, no leds, neither my GPU power supply led that normally is green when operational and red when there aren't connected cables to her).

I tough it was the PSU so i removed it from the PC and done the paperclip test and it powered himself and 4 fans attached to it on, after that I stopped testing because I am afraid it could be a faulty motherboard and thought further testing could ruin other components.

Notes:

• I don't have another compatible PSU nor digital multi-meter/PSU tester;
• All the components are minimum 2 years old so no warranty;
• When up and running all temps where normal (40-45 CPU, 30-35 GPU);
• When case fans weren't working, CPU temps raised 50-55 (the liquid cooler and his fans where working) so nothing that the CPU couldn't handle;
• I tried identifying from where there was burning smell but the liquid cooler fans were on so the only place when i could've smelt some residue were near radiator fans (top of the case);
• On the motherboard there aren't any visible burn marks.

PC Specs:

• Motherboard: MSI x570 Gaming Edge Wifi;
• CPU: AMD Ryzen 7 3700x;
• RAM: XPG Spectrix D41 (2x8GB - 3200MHz);
• PSU: Thermaltake Toughpower Grand RGB 850W (80+ Gold);
• GPU: Zotac AMP Extreme GTX 1070;
• CPU Cooling: Cooler Master MasterLiquid ML240L RGB
• Others: 2xWD Blue - 1xKingston a2000 (NVME SSD) - 1xSamsung 850 Evo (Sata SSD) - 2x200mm ARGB Fans - 1x140mm Fan - Cooler Master C500P Case.

Any help is appreciated, sorry for the long read and for my English, I am Italian.

 

[CountMike]

Last Friday my case fans (connected to the motherboard through a 3 way splitter) stopped working so i started troubleshooting, I started disconnecting the fans from the splitter and after the first fan removed the others powered back on, after a while I smelt burning smell so I immediately turned off the PC and disconnected the splitter from the motherboard and connected it to the PSU with a molex to 3pin fan connector and fully powered the PC, even tried running a game for 30 minutes and everything seemed fine.

I power off the PC and moved it to the main workstation, no sign of life when pressing the power on button so i tried toggling on/off the PSU and removing the power cord a few times and then fully started and worked like noting happened. The next day (Saturday) again the pc powered on correctly and ran fine for 16hours then I power it off to go to sleep, this was the last time it was running because today (Sunday) no sign of life when trying to power it on (no fans, no leds, neither my GPU power supply led that normally is green when operational and red when there aren't connected cables to her).

I tough it was the PSU so i removed it from the PC and done the paperclip test and it powered himself and 4 fans attached to it on, after that I stopped testing because I am afraid it could be a faulty motherboard and thought further testing could ruin other components.

Notes:

• I don't have another compatible PSU nor digital multi-meter/PSU tester;
• All the components are minimum 2 years old so no warranty;
• When up and running all temps where normal (40-45 CPU, 30-35 GPU);
• When case fans weren't working, CPU temps raised 50-55 (the liquid cooler and his fans where working) so nothing that the CPU couldn't handle;
• I tried identifying from where there was burning smell but the liquid cooler fans were on so the only place when i could've smelt some residue were near radiator fans (top of the case);
• On the motherboard there aren't any visible burn marks.

PC Specs:

• Motherboard: MSI x570 Gaming Edge Wifi;
• CPU: AMD Ryzen 7 3700x;
• RAM: XPG Spectrix D41 (2x8GB - 3200MHz);
• PSU: Thermaltake Toughpower Grand RGB 850W (80+ Gold);
• GPU: Zotac AMP Extreme GTX 1070;
• CPU Cooling: Cooler Master MasterLiquid ML240L RGB
• Others: 2xWD Blue - 1xKingston a2000 (NVME SSD) - 1xSamsung 850 Evo (Sata SSD) - 2x200mm ARGB Fans - 1x140mm Fan - Cooler Master C500P Case.

Any help is appreciated, sorry for the long read and for my English, I am Italian.

Do you have CPU cooler fan(s) connected to CPU_FAN header on the MB?
PS.
PSU may still be partially faulty even if fans are running

 

[Stephanie_Sy]

Yes CPU fan needs to be in a CPU fan header. Then just plug other fans into the closest headers in the motherboard.

 

[Greeko85]

It could be that the psu is beginning to fail; the capacitors are not discharging properly and when you try to turn on your pc the +5v signal is irregular preventing a boot sequence from initiating. If you unplug your system from the wall, leave it for a few hours will eventually cause them to discharge but its not a solution; if I'm correct the psu will fail completely sooner rather than later.

 

[LatinoF]

Do you have CPU cooler fan(s) connected to CPU_FAN header on the MB?
PS.
PSU may still be partially faulty even if fans are running

Yes the CPU fans are connected to the CPU Fan Header.
I know that even if fans are running the PSU may be faulty, the paper clip test was just to verify that it could power himself.

 

[LatinoF]

Yes CPU fan needs to be in a CPU fan header. Then just plug other fans into the closest headers in the motherboard.

The CPU fans are already connected to the CPU Fan Header (they never stopped running), the case fans where connected to a System Fan Header trough the splitter (mainly because without the splitter all of them couldent reach the mb headers), after the burning smell I removed the fans from the motherboard and connected them directly to the PSU through a molex adapter.

 

[LatinoF]

It could be that the psu is beginning to fail; the capacitors are not discharging properly and when you try to turn on your pc the +5v signal is irregular preventing a boot sequence from initiating. If you unplug your system from the wall, leave it for a few hours will eventually cause them to discharge but its not a solution; if I'm correct the psu will fail completely sooner rather than later.

So could I rule out a faulty motherboard? I have tough of buying a new one, but if the motherboard isn't the problem I would try connecting the PC in another wall plug but right now I am afraid that if the motherboard is the problem, it could damage other components during tests or even if I buy a new PSU.

 

[Greeko85]

So could I rule out a faulty motherboard? I have tough of buying a new one, but if the motherboard isn't the problem I would try connecting the PC in another wall plug but right now I am afraid that if the motherboard is the problem, it could damage other components during tests or even if I buy a new PSU.

Imo I don't believe the mobo is at fault here; do you have a friend where you could borrow a psu from just for testing purposes?

 

[LatinoF]

Imo I don't believe the mobo is at fault here; do you have a friend where you could borrow a psu from just for testing purposes?

Unfortunately no, if i could get hands on a PSU tester that could verify the voltages of the PSU various connectors so if the psu is faulty it should show, but what if the PSU voltages are in range but can't draw enough wattage even for POST to happen?

 

[DSzymborski]

Unfortunately no, if i could get hands on a PSU tester that could verify the voltages of the PSU various connectors so if the psu is faulty it should show, but what if the PSU voltages are in range but can't draw enough wattage even for POST to happen?

Unfortunately, you'd really need a full load tester to properly check out a PSU. If you can't borrow a PSU, you could get one from somewhere that allows returns on the PSU. I'd swap out the PSU before the motherboard simply because the PSU is the safety equipment and a bad motherboard can be caused by the bad PSU in the first place.

 

[CountMike]

Unfortunately no, if i could get hands on a PSU tester that could verify the voltages of the PSU various connectors so if the psu is faulty it should show, but what if the PSU voltages are in range but can't draw enough wattage even for POST to happen?

That's where serious testers come in, they can set appropriate loads for ever lead.

 

[LatinoF]

Unfortunately, you'd really need a full load tester to properly check out a PSU. If you can't borrow a PSU, you could get one from somewhere that allows returns on the PSU. I'd swap out the PSU before the motherboard simply because the PSU is the safety equipment and a bad motherboard can be caused by the bad PSU in the first place.

Understood.
Instead, do you think that a bad wall plug can be causing these issues?

 

[DSzymborski]

Understood.
Instead, do you think that a bad wall plug can be causing these issues?

Unless you see other issues, this is probably not the case. Though it never hurts to check things with a multimeter. You probably know the status of your house's wiring than I do!

 

[LatinoF]

So today I got my hands on a PSU tester, I checked all the connectors and the voltages are fine.
Do you think it is safe to do light load tests just to rule out the motherboard or just directly buy a new PSU?

 

[DSzymborski]

So today I got my hands on a PSU tester, I checked all the connectors and the voltages are fine.
Do you think it is safe to do light load tests just to rule out the motherboard or just directly buy a new PSU?

Those little PSU testers aren't load testers. They only can confirm if a PSU is completely dead.

This would be the equipment you would actually need to properly test a PSU.

I would use a new PSU from a place with a good return policy. First test a new PSU, then test a new PSU with a new motherboard. Only good way to rule out both unless you have other motherboard/GPU you can swap into the machine that are known to be working.

 

[LatinoF]

Those little PSU testers aren't load testers. They only can confirm if a PSU is completely dead.

This would be the equipment you would actually need to properly test a PSU.

I would use a new PSU from a place with a good return policy. First test a new PSU, then test a new PSU with a new motherboard. Only good way to rule out both unless you have other motherboard/GPU you can swap into the machine that are known to be working.

Yes I know that those little things can't do a full test, but I have seen them find the worst cases so I thought just to try and see the results.

 

[LatinoF]

Today, I decided to continuing testing with the things I have starting booting the PC with minimal components and adding components to see what would happen, during tests I found out that the burning smell came from a case fan (it is possible to smell it right in the center), so I thought that the PSU would go in short circuit protection and prevent me from powering on the whole system so I removed the fan from it.

At the moment the PC is up and running, I turned it on and off many times and so far all of the boot sequencies were successful, in addition MSI Center provide me the motherboard voltages readings in real-time and they all seems to be in range.

I'll continue to use the pc and monitor the situation, I will update you in a week, unless something bad shows up.

Thank you all for you time and effort, I hope it was just the fan.

 

[CountMike]

Today, I decided to continuing testing with the things I have starting booting the PC with minimal components and adding components to see what would happen, during tests I found out that the burning smell came from a case fan (it is possible to smell it right in the center), so I thought that the PSU would go in short circuit protection and prevent me from powering on the whole system so I removed the fan from it.

At the moment the PC is up and running, I turned it on and off many times and so far all of the boot sequencies were successful, in addition MSI Center provide me the motherboard voltages readings in real-time and they all seems to be in range.

I'll continue to use the pc and monitor the situation, I will update you in a week, unless something bad shows up.

Thank you all for you time and effort, I hope it was just the fan.

Fun with a fan eh ? Get rid of it.

 

[LatinoF]

Its been more than a week, removing the damaged fan solved the issue, the PC is working fine and all the boots were successful without problems.

Tank you all again.