[SOLVED] Computer shuts down randomly and restarts by itself

[Mathhguy]

Hi there.

I am trying to isolate what piece of hardware is failing on my setup, triggering random restarts (error id 41: kernel power). I get no BSOD, no error message, nothing. Just a random restart.
No matter if CPU is on load or not, the crash can occur at any time. It happened with heavy load, and also it happened with no software running besides the OS (windows 10). Its completely random. The time range between a shutdown and the next one varies from 2-3 hours until 48. The shutdowns appeared a month ago.
What I've done so far is:

1. Changed the SSD (the old one got damaged because the random shutdowns).
2. Tested ram for several hours with memtest86. Everything is ok, no errors.
3. Stressed CPU, stressed GPU, monitorized temps. Temps are okay (CPU between 30ºC at idle and 65ºC under prime95 stress, GPU between 35ºC and 64ºC).
4. Tested the GPU, RAM, HDD (disconnecting and removing them and running the computer until a shutdown happened again, which did). Tested each piece individually.
5. Monitored everything with HWinfo until an unexpected shutdown occurs. The log can be found here, and can be readed with this tool. I've checked the data and everything seems fine to my eyes but i am a bit unexperienced with hardware failure.
6. Checked the voltage lecture with HWinfo, evereything seems fine to my eyes. The log is included in 5.
7. Checked the system event viewer, no errors before the shutdown happens.
8. I did a fresh windows install just in case of a rare error. But still happens.

Everything runs smooth and fine, I can play heavy load games, render, watch movies, whatever. But then, randomly, the random shutdown happens. Temps are fine. Reinstalled CPU & Heatsinc. Installed an extra fan dedicated to the PSU in case of PSU-overheating, but the crash still happens. I think we are between PSU, CPU and motherboard, but I don't know how to test further the PSU or CPU more than check PSU voltages&temps and stress CPU monitoring temps. I could change the PSU with anotherh PSU I have but only has a 4 pin connector, and my cpu requires 4+4.
Any idea or suggestion is greatly appreciated.

Specs:
CPU: i7-4790k no OC
GPU: GTX 1070 ti
Motherboard: Gigabyte z97p-d3
Ram: x2 4 GB PC3-14900 DDR3 SDRAM G Skill F3-14900CL9 + 4 GB PC3-12800 DDR3 SDRAM SK Hynix + 8 GB PC3-10600 DDR3 SDRAM Kingston
SSD: Crucial CT500MX
PSU: Silverstone 700w Platinum 80 plus
Cooling with 4+1 fans: 2 intake and 2 exhaust and a Evo 212 for the CPU.

 

[rgd1101]

make and model of the psu?

 

[Mathhguy]

Sorry I forget to write it: PSU: Silverstone 700w Platinum 80 plus. PSU is one and half year old.
Added it on the first post.

 

[Mathhguy]

Update: The new SSD also died because thee random shutdowns. Got a PSU of 450W from a friend to test if its the PSU. Had to remove the external GPU since the backup PSU doesn't have a connector for it. It's been running for almost 24h without a shutdown.

 

[rgd1101]

sound like could be psu or gpu issue.

 

[Mathhguy]

Already tested GPU, read 4. on the first post. Can a CPU give these kind of errors? And motherboard? PSU is giving the correct voltages and temps are fine. But I also suspect from the PSU. I would like to discard the CPU or mobo someway.

 

[johnupham80]

if you got no bsod error code, try checking "view reliability history" on windows search and find what caused your pc shut down randomly

 

[Mathhguy]

There is no software-related cause. Windows reliabilty history simply shows a kernel power error, "the previous system shutdown was unexpected". I've been switching between PSU's, the one I got from my friend and mine. With my friend's PSU I got no shutdowns for almost 24h. I switched to my PSU and I got 2-3 shutdowns. The thing is, my friend psu only has a 4 pin connector and my PSU&CPU has 8 pin connector. i.e: I've been running the computer with a psu with 4 pin connector and no shutdowns. This makes me think in two posibilities:

1. The CPU or MOBO can be faulty instead of the PSU since maybe, because my friend's PSU only has 4 pin connector, is not carrying that much power as my PSU to make the mobo or cpu fail.
2. My PSU is damaged.

I don't have proper studies on hardware or electronics so I don't know how true is my assumption 1... Any idea or suggestion is greatly appreciated.

 

[johnupham80]

There is no software-related cause. Windows reliabilty history simply shows a kernel power error, "the previous system shutdown was unexpected". I've been switching between PSU's, the one I got from my friend and mine. With my friend's PSU I got no shutdowns for almost 24h. I switched to my PSU and I got 2-3 shutdowns. The thing is, my friend psu only has a 4 pin connector and my PSU&CPU has 8 pin connector. i.e: I've been running the computer with a psu with 4 pin connector and no shutdowns. This makes me think in two posibilities:

1. The CPU or MOBO can be faulty instead of the PSU since maybe, because my friend's PSU only has 4 pin connector, is not carrying that much power as my PSU to make the mobo or cpu fail.
2. My PSU is damaged.

I don't have proper studies on hardware or electronics so I don't know how true is my assumption 1... Any idea or suggestion is greatly appreciated.

maybe bcus on that heavy load your psu cant handle so many voltage that come from your hardware
if the cpu,mobo,or your other hardware not psu, it will bring you to BSOD screen
if no bsod then maybe your psu defective

 

[johnupham80]

here the list of error code https://www.lifewire.com/blue-screen-error-codes-4065576 so you can find what causing it
try this https://forums.tomshardware.com/faq/how-to-fix-windows-10-error-event-id-41-‘kernel-power’.2752245/

 

[Mathhguy]

My PSU is the model Silverstone 700w Platinum 80 plus. My friend's PSU is tacens IV 450W. Since it hasnt a 8 pin pci connector I removed my gpu. So far, with my Friends psu i dont have the shutdown issue. I already tried everything on that link. I am going to try to test my PSU on my friend's computer. I dont think is CPU related or mobo, although I think i killed the integrated GPU.

 

[Mathhguy]

Update: 3 days running with my friend's PSU without problems. From what we already have I blame the PSU. Tomorrow I will get a new one. Btw I opened and tested my PSU in my lab with a multimeter, all voltages were fine, no sign of scroth on any component, the magnetic field on the wires was in the range offered by Silverstone. Weird.

It seems the faulty PSU killed not only my ssd, but also my IGPU. My i7-4790k has an intel 4600 hd integrated GPU. Everytime I install drivers for this GPU, computers crash at windows login screen. No matter what version, tried like 6 versions including all drivers offered by Gigabyte's website. Tried it in windows 7/10 fresh install and ubuntu, all OS crashing after few seconds of logging/startup screen. With windows default drivers it doesnt crash (basic microsoft display adapter) idk why. Luckily I can still use my cpu without problems with my 1070 ti (it also can be the internal mobo circuit for the GPU the one who got damaged but I doubt it since there is no visible signs of damage and because I can run the internal intel GPU without drivers).

 

[computermonkey]

Tried it in windows 7/10 fresh install and ubuntu, all OS crashing after few seconds of logging/startup screen. With windows default drivers it doesnt crash (basic microsoft display adapter) idk why.

Did you use proprietary drivers for unbuntu or the basic open source ones that are used by default?

 

[Mathhguy]

Did you use proprietary drivers for unbuntu or the basic open source ones that are used by default?

I have no idea, didnt even have time to check... I downloaded Ubuntu 18.04.4 LTS version. From what I could gather comes with i915 kernel drive.

 

[Mathhguy]

Solved: the gpu was faulty. How? No idea... Voltages were good, magnetic field inside was okay, no overheat... Capacitors were okay... Its solved but meh, I would like a lot to know what was faulty, just for curiosity. Anyway thanks to& all.