Question PC boots straight into BIOS and does not detect any bootable devices

[Spades0]

Windows was updating this morning when I left for work. When I came home this afternoon and turned my PC on it boots straight into the BIOS. Not a single one of my drives (two sata SSDs, one HDD and one NVMe drive) shows up as a bootable option. I tried unplugging the SSDs and putting them back in but no luck... I inserted a USB stick which did show up in the boot menu but nothing else... could the motherboard be damaged? Is there anything else I can try?

Many thanks!

 

[Lutfij]

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:

include the BIOS version for your motherboard at this moment of time.

 

[rickypicky5]

If it's not recognizing any of your disks, try doing a clear CMOS.

 

[Spades0]

Hi all,

So sorry for the slow response. I found a fix by enabling CSM boot. However, since that first incident, I have had to do this every time now I switch on my PC after turning it off overnight. The PC also doesn't just start up; it turns on for a few seconds, turns off and on again by itself, and this repeats a few times. An orange light appears on the mobo that turns red every time. Eventually, after this happened a few times, the orange light turns white and the computer enters the bios. After enabling CSM boot again, the computer restarts one more time and boots into Windows 10 and remains very stable for the entire session I use it. The next day the ritual repeats itself. My PC clock also loses some time overnight when switched off. Could all of this be because of a dead CMOS battery?

PC specs:

ASUS ROG Strix Z390-F Intel Motherboard
Intel 9th Gen Core i7 9700 Up to 4.7GHz CPU
Corsair Vengeance RGB PRO 16GB 3200MHz Gaming Memory

Antec HCG850 Bronze 850W Modular Power Supply / 80 Plus Bronze / 100% Modular / CircuitShield / 135 mm (DBB) Fan / Engergy Efficiency / 100% Japanese capacitors / HCG850Bronze

GPU RTX3080

Windows 10

 

[Richj444]

Hi all,

So sorry for the slow response. I found a fix by enabling CSM boot. However, since that first incident, I have had to do this every time now I switch on my PC after turning it off overnight. The PC also doesn't just start up; it turns on for a few seconds, turns off and on again by itself, and this repeats a few times. An orange light appears on the mobo that turns red every time. Eventually, after this happened a few times, the orange light turns white and the computer enters the bios. After enabling CSM boot again, the computer restarts one more time and boots into Windows 10 and remains very stable for the entire session I use it. The next day the ritual repeats itself. My PC clock also loses some time overnight when switched off. Could all of this be because of a dead CMOS battery?

PC specs:

ASUS ROG Strix Z390-F Intel Motherboard
Intel 9th Gen Core i7 9700 Up to 4.7GHz CPU
Corsair Vengeance RGB PRO 16GB 3200MHz Gaming Memory

Antec HCG850 Bronze 850W Modular Power Supply / 80 Plus Bronze / 100% Modular / CircuitShield / 135 mm (DBB) Fan / Engergy Efficiency / 100% Japanese capacitors / HCG850Bronze

GPU RTX3080

Windows 10

Sure sounds like a dead CMOS battery to me.