Computer randomly restarting (NO BSOD)

Hey!

Since yesterday, my computer has been radomly restarting without any warnings. Sometimes it restarts when I'm on the motherboard first screen (the screen that appears when computer starts). I don't think it's overheating, because the first time I've started it today it shut down after 2 minutes. Also the fans doesn't stop working when the computer restarts and there's no "Blue Screen of Death", it just restarts without any warnigs.

I've built this computer on July, PSU and RAM are from my brother old computer.

CPU: Intel Core i3-4160 CPU @ 3.60GHz
GPU: Gigabyte GeForce GTX 960 WindForce 2GB
Motherboard: B85-G41 PC MATE (MSI)
PSU: Corsair TX650W
RAM: 3x 2GB DDR3

What could be causing it? I just can't do anything on that PC...
Thanks!

unrealRage said:

Hello & welcome!

Your power supply might be failing.
Check voltages in BIOS and post them here.

Place RAM sticks differently in slots or remove stick by stick and see will it randomly restart.

Also, are you sure that computer isn't overheating?
Go to BIOS >Check temps >Let it sit and check are temps gradually rising.
Have cleaned your computer recently?

Hey, hope you still can help me since I didn't answered you for some days. :)

Here are the voltages (hope that is it, never ever touched a BIOS screen :P):


RAM sticks are all fine.

And a thing I've noticed about overheating - right after I turned on the computer for the first time on the day, I went to the BIOS screen and noticed CPU was 80ºC, then I was able to enter the desktop without computer restarting, runned speccy and CPU was 40ºC... Don't know what to trust to be honest. :\

Thanks for your help!

Mellon Head said:

I would suspect the power supply or the RAM, as unrealRage has mentioned.

I would check the RAM with a utility like Memtest86+. Let it run for eight passes, preferably over night, but watch the first couple to see if it spontaneously reboots.

Here is where you can get the program:

Memtest86+ - Advanced Memory Diagnostic Tool

The thing is I can't run it since my computer keeps restarting randomly... It will most likely restart on them middle of the test...

Thanks anyway! :)

Mellon Head said:

Open your computer and make sure that your heat sink/fan is securely attached to your CPU, and that it is fitting in the bracket properly.

A BIOS temp reading of 87C on your CPU is way too hot. Speccy might be reading wrong. Your BIOS should be right, unless you have a failed sensor.

I will go buy thermal paste now and apply it, just tell me a thing since I'm not an expert (not even close to it) on computers. I must wait a few days for the thermal paste to make effect or it will be instantly after I applied it?

The fan is securely attached to my CPU, I've checked it yesterday. :)
And are you sure it is possible to get 80ºC on the CPU 15 seconds after turning the computer on for the first time? Because my BIOS tells that my CPU has that temperature right after turning my computer on for the first time on the day.

Thanks for your help, once again!

Mellon Head said:

Open your computer and make sure that your heat sink/fan is securely attached to your CPU, and that it is fitting in the bracket properly.

A BIOS temp reading of 87C on your CPU is way too hot. Speccy might be reading wrong. Your BIOS should be right, unless you have a failed sensor.

I've applied the thermal paste and the CPU temperature doesn't go above 40ºC now, but computer still restarting randomly. Most likely PSU, right? Any way to know if that's it or no? I don't have another PSU or anyone with desktop computers to lend me a PSU... :\

bigmck said:

Hypermega said:

Mellon Head said:

Open your computer and make sure that your heat sink/fan is securely attached to your CPU, and that it is fitting in the bracket properly.

A BIOS temp reading of 87C on your CPU is way too hot. Speccy might be reading wrong. Your BIOS should be right, unless you have a failed sensor.

I've applied the thermal paste and the CPU temperature doesn't go above 40ºC now, but computer still restarting randomly. Most likely PSU, right? Any way to know if that's it or no? I don't have another PSU or anyone with desktop computers to lend me a PSU... :\

Check both the Bios and Speccy to see if the temp agrees? If they do, I would think the PSU is failing. How long have you had it? A new one can fail, but the older it is, the more likely it could fail. If you have had it for four or five years, I think it would be time for a new one. The Corsair that you have is a good brand. I have that also. Let us know the Speccy and Bios temp.

Hello!

I've reused my PSU and RAM from my brother's old computer, don't know the exact date of when the PSU was bought, but I'm nearly sure it's 5+ years. On the BIOS the temperature doesn't go above 40ºC since yesterday, when I applied new thermal paste. And I can't check on speccy now because the restarts don't let me.

I can buy a new PSU, but I really want to make sure that it is the PSU that is failing, since I am saving for an SSD and buying a new PSU when it still won't work would be absurd.

Thanks for your help! :)