PC Occasionally does not post. After a few power cycles, the CMOS Resets, and the PC boots normally.

[nathantibbitts]

Sometimes my laptop cycles on and off when powering up and won't POST. There are no beep codes, or anything like that to indicate what the error is. I ran a Memtester, both the UEFI one and an ISO of Memtest86+. No errors in the RAM itself, though when I change it, or sometimes randomly, the above listed event occurs. The Linux tool `cat /proc/drivers/rtc | grep -i batt` reports that the status of the CMOS battery is "okay" (Which means there aren't errors if you are unfamiliar with Linux parlance). 

It won't even POST to the UEFI. The fans spin up, and then the machine shuts itself off.  After the CMOS resets itself with error 502, the machine posts and boots properly. 

What could cause this? Is there any way I can fix it?

I am both the user and the technician in this case.