502 error, cmos checksum invalid

[letcheta]

Hi,

My gaming laptop keeps shutting down unexpectedly.

I need to wait a long time (more than 2 hours)  to get it booted again. immediate power up after auto power off, is always failing,  screen don't even appear.

After a long wait, I see cmos 502 error, checksum invalid. I got this error from original bios, because of it ,I upgraded it 2 times now to F.55 . this migration make things worst, because when it boots normally to operating system, after 15 minutes,  the PC is halted and at least 2 hours is required to to make an attempt.

Note that downgrading always fails due to signature error.

Is my motherboard which breaks ?

thanks.

[ub6424]

Hello @letcheta 

The CMOS battery (CR2032) has to checked and replaced.

best regards

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[letcheta]

Hi @Lewis,

I forgot to mention that after this error, I need 2 hours or more to reboot my PC. when I try to immediately reboot, power key just light on for few seconds and then stop. same result for more than 10 continuous attempts.

More I tried to restore bios using USB key, downgrading, but it fails due to signature. 

I think the motherboard is broken. By the way, I am a computer engineer with 11 years of experience. 

I think HP is not reliable as other major brands. 

Thanks