random reboot's

[Pectacq]

Hi,

I have a issue with my pc.

It wil random reboot my pc, it wil freeze and every thing goes to black and then it wil reboot just normal(not bluescreen orso)

i dont know whats causing this problem.

i am running bios 0210 on C8 Dark Hero with R7 5800X and RTX 3080 TUF OC and a corsair rm850i power supply

[xeromist]

Have you run memory stability tests? HCI Memtest is my go to lately and it's free. Just make sure to open enough copies to fill your memory and let it run overnight.

[Englishman.Xperia]

Check if you have an error code on the board or somekind of led. I'm also facing some crashes while gaming and the DRAM light pops up.

But just like xeromist said, I would start with a long memtest86 session followed by some stress tests on CPU and after some on GPU to isolate the problem.

[BigJohnny]

nearly all issues that result in a freeze are memory related.
You can run memtest86 or windows has a memory test just Windows Key+R, type “mdsched.exe" then reboot. It doesnt bang the memory like memtest does but if it doesnt pass that its much shorter and a good point to start.

[DCTech]

You may want to try:

edit: Confirm your BIOS version, current BIOS for C8 Dark Hero is 3801 and if that's not what you have then update BIOS first.

1) Reset BIOS to defaults and only make necessary changes like FAN settings (ex: enable PWM if you have appropriate fans to avoid jet engines from taking off) and enable DOCP/XMP if your RAM supports it. Is your RAM model on QVL for this board? If it's not then it's a hit to miss territory.
2) Look at your Win system event log, are there any messages of interest? Kernel panic or others?
3) Test your RAM with Win build in RAM test tool or MemTest86, if fails try disabling DOCP/XMP in BIOS (if enabled) and test again.
4) Watch your CPU temp with a tool like CoreTemp and use a CPU bench/test tool like OCCT or Prime95. You may want to do this from Win safe-mode so that NV drivers are not loaded as the problem may be on GPU side.
5) If above pass and CPU stays in rated temps then look at GPU next. Before running any stress tests on GPU with tool like OCCT make sure you are using separate PCI-E power cables for each external power plug on the GPU. These NV ..80 series GPUs pull A LOT of power which can melt PCI-E daisy chained power connector! Not kidding happened to me once with a GTX card and I've learned my lesson since. I wish PSU mfg. stopped adding these little daisy chain ends on these 6/8 PIN PCI-E power cables. Your build looks cleaner with a daisy chain PCI-E cable until you see smoke or fire from the case and come PSUs may not provide enough power on that rail causing instability :/