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- Notebook Boot and Lockup
- CMOS 502 error following latest BIOS update

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12-21-2018 02:52 AM
The laptop was new at the end of August 2018.
A few days ago the HP Support Assistant providied a BIOS update which I installed.
Since then on power up I first get the power switch light flashing, then the light on the caps lock button give 3 long and 5 short flashes which I understand says it can't find the CPU.
Forcing a power off, waiting the n powering on again gives "The CMOS checksum is invalid." CMOS 502.
Press enter to rest and the computer starts and runs fine.
I assume that the BIOS updtae is invalid, or has not installed correctly (all done through HP Support assistant).
Any advice and a fix greatly appreciated
Solved! Go to Solution.
Accepted Solutions
12-21-2018
03:26 AM
- last edited on
08-21-2024
06:56 AM
by
JessikaV
Hi
https://support.hp.com/us-en/document/ish_3932413-2337994-16
Hardware |
3.5 |
The processor is not detected.*
Indicates potential CPU failure. |
1 If able, reseat CPU. 2 If able, test known good CPU. 3 Replace affected component. 4 Replace CPU & Main-Board if unable to perform steps. |
You are correct.
12-21-2018
03:26 AM
- last edited on
08-21-2024
06:56 AM
by
JessikaV
Hi
https://support.hp.com/us-en/document/ish_3932413-2337994-16
Hardware |
3.5 |
The processor is not detected.*
Indicates potential CPU failure. |
1 If able, reseat CPU. 2 If able, test known good CPU. 3 Replace affected component. 4 Replace CPU & Main-Board if unable to perform steps. |
You are correct.
12-21-2018 07:48 AM
@Lil_Boy_Blue wrote:Hi
https://support.hp.com/us-en/document/c02693833
Hardware
3.5
The processor is not detected.*
Indicates potential CPU failure.
1 If able, reseat CPU.
2 If able, test known good CPU.
3 Replace affected component.
4 Replace CPU & Main-Board if unable to perform steps.
You are correct.
Thank you for the link. This seems to have worked successfully.