Question Asus Z10PE-D8 WS mobo computer wont fire up

[cameronjpu]

So I was troubleshooting a computer today and I am totally stumped. Computer has not been turned on for about 18 months but worked prior. Upon first boot, computer could not find boot option for Windows. Hotkey to boot menu did nothing. Only F key that worked was the one to go to the BIOS. Looking in the BIOS, nothing interesting. Boot order looks fine. Upon reboot, the system spontaneously reboots after 5 seconds repeatedly. Code 24 is the code on the mobo LED when it shuts down.

Pulling power cable or switching off PSU so that power can drain (no need to pull CMOS battery) results in system again being able to boot back into BIOS setup. But again, after any changes, continual reboots at code 24.

Pulled RAM and tested fine. Pulled CMOS battery and replaced. Pulled video card and replaced. Nothing changes behavior.

Any ideas on what to try next? I'm stumped.

 

[popatim]

Clear your cmos per direction in your manual please.

 

[cameronjpu]

Clear your cmos per direction in your manual please.

The CMOS clears every time I pull the power cable. All settings that I change are reset to factory at that point. That's the weird thing. Doesn't take any special procedure. That's why I replaced the CMOS battery because I couldn't see any other reason why that would happen. I also updated the BIOS to current (2020) from 2015.