Question PC boots into BIOS if I dont use it for 2 to 3 days, but works fine (boots into windows) if I use it daily. Note: I unplug my PC from power socket.

[Ali Anas]

built my PC new, around 2 months back and it worked fine till now, this weird issue is occurring since a week or two. I highly doubt if its CMOS battery.

Windows 10 64 Bit. UEFI. CSM is disabled. Boot priority is set to Windows Boot Manager first.

Motherboard: Gigabyte B550M-K (BIOS: F1)
Processor: Ryzen 5 5600
RAM: Tforce Delta 8GBx2
GPU: NVIDIA GEFORCE RTX 3070
NVME: Lexar 500GB
SATA SSD: Team Group 1 TB

Initially the CSM was not disabled. And it worked fine, and one day it gave me an error "reboot and select proper boot device or insert boot media in selected boot device and press a key", again, I just used to reboot my PC and it worked fine (booted into windows), my vendor told me to disable CSM. But since when I've disabled CSM, it doesn't give me this error, but boots into BIOS if I dont use my PC for 2 to 3 days (yes, it remains unplugged) and "reboot and select proper boot device' error also occurred only when PC stayed unplugged for more than 1 or 2 days. Weird! Help please.

 

[rgd1101]

brand and model of the psu?
after you turn the pc off, do you unplug the pc from the power outlet?

 

[Ali Anas]

brand and model of the psu?
after you turn the pc off, do you unplug the pc from the power outlet?

PSU is Deepcool 750W 80+ Bronze. Yes, I unplug the PC from power outlet always.

 

[Order 66]

PSU is Deepcool 750W 80+ Bronze. Yes, I unplug the PC from power outlet always.

specific model of PSU? even some great PSU makers have lineups of PSUs that are junk.

 

[rgd1101]

why do you doubt is the cmos battery?
try turning off fast boot in bios?

 

[Ali Anas]

specific model of PSU? even some great PSU makers have lineups of PSUs that are junk.

DeepCool PK750D​

 

[Order 66]

DeepCool PK750D​

while that PSU is not the greatest, I don't think that it is the cause of your problem, with that said, I would try a different PSU and see if the issue persists.

 

[Ali Anas]

why do you doubt is the cmos battery?
try turning off fast boot in bios?

Fast Boot is already disabled

 

[Bob.B]

built my PC new, around 2 months back and it worked fine till now, this weird issue is occurring since a week or two. I highly doubt if its CMOS battery.

Windows 10 64 Bit. UEFI. CSM is disabled. Boot priority is set to Windows Boot Manager first.

Motherboard: Gigabyte B550M-K (BIOS: F1)
Processor: Ryzen 5 5600
RAM: Tforce Delta 8GBx2
GPU: NVIDIA GEFORCE RTX 3070
NVME: Lexar 500GB
SATA SSD: Team Group 1 TB

Initially the CSM was not disabled. And it worked fine, and one day it gave me an error "reboot and select proper boot device or insert boot media in selected boot device and press a key", again, I just used to reboot my PC and it worked fine (booted into windows), my vendor told me to disable CSM. But since when I've disabled CSM, it doesn't give me this error, but boots into BIOS if I dont use my PC for 2 to 3 days (yes, it remains unplugged) and "reboot and select proper boot device' error also occurred only when PC stayed unplugged for more than 1 or 2 days. Weird! Help please.

Change the bios bat.......their cheap.

 

[Ali Anas]

Change the bios bat.......their cheap.

I changed the CMOS battery yesterday. Using Panasonic Lithium CR2032 now. I replaced the battery and tested twice after unplugging. Both the times PC booted successfully into windows. Checked on intervals of 3 hours and 13 hours. It's fine till now so far.

But I will update you after a week of testing. Let's see.