My PC running Windows 10 shuts down after exactly 10 minutes after powering it on.
After that, I have to enter BIOS. I can boot with the exact same settings as before, and it will run for weeks without problems. This only happens with the first start, after it restarted it will work indefinetely.
If I shut it down and let it rest for like 2 hours, the problem occurs again at the next power on.

What in the fuck could this be?
It is definitely not a temperature problem, the whole system is water cooled and temperatures are perfectly fine.
The system is literally days of linx, prime furmark and 3dmark stable.
I assumed it could be because of overclocking, but it occurs at default values as well.
I changed secure boot options, but it doesn't seem to help.
There is no mention of the problem in the event log, sometimes it states "system shut down unexpectedly", but most of the time it's just empty.
I changed graphics card several times to no avail.

Any ideas?

Hardware I am using:
Gigabyte Z97X-SOC Force
i7 4790K
Evga GTX 1080
4x4GiB Corsair Dominator Platinum DDR3
Corsair AX750
Crucial MX100 512MB
Also a few HDDs using hot plug so they shut off a minute after boot and only spin up when needed.
Windows 10 Pro with the latest updates. Problem has been occuring for a few months.