Computer sometimes POSTs

[Tan3l6]

A while back my PC has started failing POST. The way I instantly know it's a failed boot is the "double beep":

https://streamable.com/xp016r

 

After pressing reset button it sometimes posts. Sometimes it takes 2-5+ presses to get the machine working.

I'm suspecting it to be some motherboard fault. Just thought to ask - any advice?

It is 100% stable when it POSTs.

 

CPU - i5-10600K
Motherboard - Asus TUF-GAMING-Z490-PLUS
RAM - 2x8GB 3000Mhz DDR4 Crucial Ballistix (Micron E-die)
GPU - MSI GTX 1060 3GB
Case - Modecom Harry 3
Mains storage - 1TB Adata SX8200 Pro
PSU - Corsair RM1000x

[Middcore]

I am immediately suspicious of that SX8200 Pro because I had one as a boot drive in a system that just failed after a mere six months.

 

For me the symptoms were the PC freezing with the hard drive activity light on the case stuck on (rather than blinking), "WHEA UNCORRECTABLE ERROR" or "UNEXPECTED STORE EXCEPTION" blue screens, and the drive failing to be detected on boot ("Reboot and select proper boot device") until I had reset the CMOS multiple times.

 

 

[Tan3l6]

3 minutes ago, Middcore said:

I am immediately suspicious of that SX8200 Pro because I had one as a boot drive in a system that just failed after a mere six months.

 

Yeah I had anomalies with my first SX 8200 Pro also, but this current one has been solid for over a year. Everything is stable and no strange freezes when machine works. 

 

Only other strange anomaly appeared couple of weeks after updating motherboard BIOS - the POST procedure is now about 10 seconds long. Used to be 2-3 seconds.

[Tan3l6]

Well an update - now it does not POST. Far from that, it does not turn on at all.

Edit:

 

After quarter of an hour, after being taken apart a bit I tried and it now works again and even POSTs sometimes, like before.

[Mark Kaine]

Can u rollback the BIOS update?

i mean that seems to be when the issue appeared so i would try to revert it.

[Tan3l6]

6 minutes ago, Mark Kaine said:

Can u rollback the BIOS update?

i mean that seems to be when the issue appeared so i would try to revert it.

I somewhat suspect that the problem was with the cmos battery, as after the system started to decide to boot again it boots after restart with no fails.

Rather I wait for a new BIOS update.

Oh, I did forgot to mention that I swapped the BIOS battery, and after 30 minutes or so the system was "brought to life".

Will run a boot test now... yeah it boots and POSTs fine but there are some other small anomalies, that I do take for the machine to be able to work mostly again.

 

Need for a replacement battery is a strange one, considering the mobo is only year old. The reason I decided to change it resulted from a wrong time after some boots, reported in Windows 10/11 by the way.

[Mark Kaine]

Ah, ok maybe it was the battery then.