Question CPU will not clock down after undervolt

[KoolerThanJesus]

A few months back I undervolted my 13700KF to get a bit more performance out of it & less heat.
Typical -0.100 undervolt, nothing special. Got the normal expected outcome. Problem is, after so many days of using my PC & putting her to sleep at night.
I noticed after 3-5 days, it will get stuck, fluctuating from 1.225-1.275 volts & the clocks will stay around 5-5.3ghz(like its overclocked or something).
I have left it on idle, nothing open but HWinfo. Sitting on desktop for 30+ mins & it will not downclock. This is repeatable after the amount of days
I have no idea what triggers this. Its not all that big of a deal as I can fix it with a simple restart but Id like to know what causes it after 4 or 5 days.
I wouldnt mind putting a stop to it.
Any help would be appreciated.
Some pics
My undervolt.

Normal working clocks

When the problem starts.

 

[Ralston18]

Update your post to include full system hardware specs and OS information.

PSU: make, model, wattage, age, condition (original to build, new, refurbished, used)?

Disk drive(s): make, model, capacity, how full?

How is the PC "put to sleep" at night?

How old is the CMOS battery?

 

[KoolerThanJesus]

Update your post to include full system hardware specs and OS information.

PSU: make, model, wattage, age, condition (original to build, new, refurbished, used)?

Disk drive(s): make, model, capacity, how full?

How is the PC "put to sleep" at night?

How old is the CMOS battery?

CPU : 13700KF
GPU : Gigabyte 4080 Super gaming OC
COOLER : Phanteks Glacier One 360T30 Gen 2
RAM : Crucial Ballistix 32GB 3600 CL16 dual-rank DDR4
MOBO : Z690 MSi Edge Wifi DDR4
M.2 : 2TB Crucial P5 Plus w/ Heatsink (OS) - SATA SSD : 2TB 860 EVO (Storage)
PSU : Corsair RM1000X (2021 model)


Windows 10.
Bios up to date
OS M.2 is 1.63TB free of 2TB
SATA SSD is 711GB free of 2TB
PC is put to sleep every night
No ideas how old the CMOS battery is. Could that actually be a factor here?

 

[Ralston18]

CMOS battery - yes.

May no longer fully capable of retaining system configuration settings while the host's power is off.

Very easy and inexpensive to replace the battery - just as a matter of elimination.

Be sure to replace the battery by following the motherboard's User Guide/Manual.

3 - 4 year old PSU: may be at or nearing its's designed in EOL and starting to falter and fail.

Take a look in Reliability History/Monitor and Event Viewer for any error codes, warnings, or even informational events being captured.

There may be some clues therein.

= = = =

And, as always should be being done, ensure that all important data is backed up at least 2 x to locations away from the host system in question. Verify that that backups are recoverable and readable.