PC Double boots on cold boot, then straight to BIOS

CTech

Ive been having some issues as of late with my Asus Strix z270e mobo, double booting into the BIOS on cold boots (after being disconnected from power - intentionally). A little history here.. I had this PC built from scratch and assembled at M.C. and have had nothing but issues with this build unfortunately. Just my luck, 2 years later and I now have this issue and my extended warranty is up.. 

This specific issue however, was only noticed recently, when the need to relocate my PC was needed and after shutting my PC down normally (via start -> shutdown), switching off the PSU and disconnecting from my UPS. The next day after moving things around I plugged everything back into my UPS, switched the power on at the PSU and power the PC on. It starts for a second, then switches itself off, and turns itself back on about 2 seconds later. When it does this, the American Megatrends screen will appear and tell me to: 

"Please enter setup to recover BIOS setting. After setting up Intel (R) Optane Memory or the RAID configuration was built, SATA mode selection must be changed to RAID mode to avoid unknown issues. Press F1 to run setup." 

The BIOS clock and date are not correct when this happens I've noticed. All I do is press F1, then save and exit from the BIOS (which no changes are made), which will then load the OS. I then login to Windows, connect to the internet and date/time is automatically updated. Everything seems fine, until the next time I disconnect from power. Please note, this issue does not occur when shutting down and keeping connected to power, then powering on. Restarts are also unaffected. I have tested this about 5 times since noticing this and have spent countless hours researching for answers on the web, even trying turning off fast boot, which does not mitigate this issue unfortunately. It happens everytime, after a shutdown and disconnect from power, then reconnecting to power and powering on. I've also noticed a couple entries for Event ID: 41 for Kernel Power in the event viewer, which seem to correlate. And also seeing a number of Event ID: 79 and 80 for AppModel-Runtime around the same timeframes but unsure whether these are related. I really hope this can be resolved as I'm starting to grow concerned of data loss and damage everytime I have to disconnect and relocate this rig.. I've sunk enough into this build already.. Hoping it's a rather small setting thats being missed but not holding my breath. No notable modifications after build other than OS updates and a few apps (Steam, Razr Chroma, Battlenet). Really appreciate any help anyone can provide here and thanks for your time. My specs:

Corsair Obsidian 750D Case

Asus STRIX Z270e mobo

Asus STRIX gtx 1080

Corsair RM750x Gold PSU

I7 7700k CPU

2 8GB sticks (16 GB total) Corsair Vengeance RGB 3000 Mhz RAM

Samsung Evo 960 500 GB M.2 SSD

Western Digital 4 TB Black HDD

Corsair Hydro 100i v2 Cooler

Win10 Pro 2004

Razr Blackwidow Chroma Keyboard

Razr DeathAdder Mouse

TSKevinG

Good Afternoon @CTech

Welcome to the Micro center Community.  Base on the information you have given and that this issue only seems to occur when the system is unplugged from the power, most likely the CMOS battery on the motherboard has gone bad.  this small battery allow the system to retain the information for the bios like the time and date, while there is no power to the motherboard.  The event you mentions in windows i believe are not related to this as for this issue the system is not booted to windows yet so it should not be  able to record the issue in the event viewer.  The Battery for the motherboard will be a coin shaped battery next to the PCI-e slots.  If you replace this then the system should hold the bios setting even if the system is unplugged an you should no longer get this message.
https://www.asus.com/us/Motherboards/ROG-STRIX-Z270E-GAMING/

CTech

Thank you for your response. I'll replace the CMOS tonight and give it a shot. The event ID's mentioned, reference shutdowns that were not clean, as well as corrupted app packages. Those unclean shutdowns correlate to the time it was shutdown and disconnected from power, which is strange.. Hoping not a case of a bad mobo/psu..