[SOLVED] PC continuously reboots itself ?

jlgsy94

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Jan 29, 2017
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I built a new PC a few weeks ago, I'll list the specs below first;

AsRock B450M-HDV
AMD Ryzen 5 3600
Nvidia GeForce GTX 1660 Super
500gb WD Blue SN550 NVMe
16GB Corsair Vengeance LPX DDR4 3600MHz
Corsair CX550 PSU

The PC was working fine up until last night when it decided to reboot itself continuously out of the blue and kept on doing so. I eventually managed to get it to boot in safe mode with networking through Command Prompt in Advanced Repair Options. I unticked Automatic Restart and then rebooted in normal mode, and for a while it was working. However it then started to reboot itself again. Eventually I managed to get it to Windows Installation screen, but half way through a fresh install it decided to reboot itself yet again.. I then finally managed to complete a fresh install of Windows. I ran a check on registry files etc but it came up with no errors. 10 minutes after that, you guessed it, it started to reboot itself again and I now don't know what to do..

I've tried clearing CMOS, reseating the RAM, using one RAM stick at a time, but the problem still persists. Could it be a PSU Or mobo problem?
 

Ralston18

Titan
Moderator
First, look in Reliability History and Event Viewer for error codes, warnings, and informational events that correspond with reboots.

Second, power down, unplug, and open the case. Double check all cables, connectors, cards, RAM, and jumpers Ensure that all are fully and firmly in place.

Making connections on a new build can be a bit tricky. No one wants to force a connection so what may initially seem to be "plugged in" is actually not and works loose thereafter. Contact is intermittent and reboots result.

Also look for cables that may be kinked, pinched, have bare metal showing - somewhere that could be causing a short.
 

jlgsy94

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Jan 29, 2017
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At this moment in time I am completely unable to boot Windows up. I've flashed BIOS and then attempted to do a fresh Windows. However, it won't even get to the country/language option prior to installation before it decides the restart itself.

I also went ahead and took out RAM sticks and replaced with one from my other PC (same brand/mhz). Problem persists. I then used the PSU from my other PC, problem persists. Then, I decided to use the NVMe from my other PC (which has a fully working Windows OS), problem persists. I managed to get hold of another motherboard (B450M-Pro4), plugged all components into that, problem persists.

That, to me, only leaves the CPU to be the possible culprit? I think I've pretty much exhausted everything else, but if you can think of something your input is very much appreciated. Otherwise, the PC will be heading to the repair shop tomorrow, which would be great to avoid as I'll be charged £££'s.
 

jlgsy94

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Jan 29, 2017
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Update:

The PC went to the repair shop Monday 22nd March and it was ready to be picked up Friday 26th March. Shop said that the Motherboard had been resting on one of the stand-off screws, which I'm guessing could have shorted it somehow? They also said they had to update BIOS. Anyways, they said they took everything apart and put it all together again and afterwards the PC was posting fine. However as there were no Windows installed on the SSD they couldn't test it further. I said that's fine as I'd just install Windows myself (Official ISO from Microsoft website on a USB).

So, I get the PC home and attempt to install Windows. It gets to 71% and the PC then starts to reboot itself again and again. This time it produced 2 different BSOD's ; KMODE_EXCEPTION_NOT_HANDLED and MACHINE_CHECK_EXCEPTION . It had gone beyond my technical skills so rather than fiddle with it, I took it back to the repair shop yesterday (Saturday 27th March). They're going to try and install windows and see if it works correctly.

I did some research and apparently MACHINE_CHECK_EXCEPTION is a hardware failure with the CPU according to Wikipedia (Machine-check exception - Wikipedia ) . I have a horrible feeling that the CPU is dead. Anyone else think the same??
 
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Deleted member 14196

Guest
Maybe all the shorting against the standoff screw did some damage to the motherboard. CPUs rarely fail
 
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Deleted member 14196

Guest
Where are you shorting that one against the motherboard too? you did say that when you took it to the shop they said that it was shorting out against the case so that means whatever you tried probably was the same result because you weren’t using the standoff screws
 
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Deleted member 14196

Guest
Breadboard it. Take it all out of the case and run it outside of the case and see if it happens if it doesn’t then your shorting against the case
 

jlgsy94

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Jan 29, 2017
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Where are you shorting that one against the motherboard too? you did say that when you took it to the shop they said that it was shorting out against the case so that means whatever you tried probably was the same result because you weren’t using the standoff screws

Breadboard it. Take it all out of the case and run it outside of the case and see if it happens if it doesn’t then your shorting against the case

Sorry I should have been more specific. I did run it outside of the case with the other motherboard prior to taking it to the shop on Monday and it still kept doing the same thing.
 

jlgsy94

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Jan 29, 2017
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Update: Shop called to say CPU was the issue, I had managed to short it with the motherboard resting on the stand-off screws... Even though it was entirely my fault, they replaced the CPU free of charge and are going to send the other one back to manufacturer, and they didn't charge me anything for their time either. Super happy, pc is working fine now and I can now declare this case closed!