I recently have built a new Desktop (Specs at the End) and I have a boot issue in which I cannot find the fix for. When I built the PC at first it was fine, booted, installed windows, checked how it ran and the temps, played a few games, etc. However one day I went to power on and the power button did not work. I then thought maybe the power cable had somehow come loose so I took it out and plugged it back in. The PC started to turn on without me pressing the power button at the top of the case and then after a few seconds it turned off. The power button on the case did not work but the reset button did and the same thing happened. I then proceeded to check all the cables inside and nothing was out of place and was plugged in. I then tried to switch the RAM ports and nothing again. I left it at that for then due to work but then came back to it the following day. I took everything out, reset the CMOS and did a basic boot where it was just the CPU, MOBO, and 1 stick of RAM. It booted to Bios and I thought I must have messed something up in the bios so I reset the Bios, tried again with the second stick of RAM and it still booted so I plugged everything back in and it worked. Now a couple of days has passed again and the same issue has happened again, however I noticed beforehand that vefore I turned the PC on that it tried to self boot again and stoppped. Today to make sure I took everything out, to see if there was a fault I missed however there seemed to be no bent pins, mobo is not grounded, cmos had been reset, everything plugged in right, nothing left out in any of the Boxes. I'm at a loss of what to do and am very frustrated with it. Sorry for the long post but if someone could see an issue with what is up then it would be greatly appreciated.
Specs:
CPU - i7 8700k
Mobo - Gigabyte Aorus Z370 Gaming 5
GPU - MSI RTX 2080 Gaming X Trio
PSU - Corsair RM750x
CPU Cooler - Corsair H100i v2
RAM - Corsair Vengeance LPX GDDR4 2x4gb
Case - Corsair Carbide Spec-06 RGB
Memory - Samsung 850 Evo 500GB SSD
Update: Took out the Motherboard recently to double check it wasn't grounded and then put everything back in. The PC booted and was completely fine for 1 night. Then the next day the same issue apart from the Motherboard RGBs were constantly on after failed boot.
Specs:
CPU - i7 8700k
Mobo - Gigabyte Aorus Z370 Gaming 5
GPU - MSI RTX 2080 Gaming X Trio
PSU - Corsair RM750x
CPU Cooler - Corsair H100i v2
RAM - Corsair Vengeance LPX GDDR4 2x4gb
Case - Corsair Carbide Spec-06 RGB
Memory - Samsung 850 Evo 500GB SSD
Update: Took out the Motherboard recently to double check it wasn't grounded and then put everything back in. The PC booted and was completely fine for 1 night. Then the next day the same issue apart from the Motherboard RGBs were constantly on after failed boot.