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HP Recommended
HP EliteBook 840 G1 Notebook PC

I get this message when I start my computer:

The CMOS checksum is invalid. The CMOS will be reset to the default configuration and will be rebooted. Please check your BIOS Setup options to see if they change.

 

CMOS Reset (502)

ENTER - Reboot system

 

If I just wait it boots up.  Computer also runs very slowly

1 ACCEPTED SOLUTION

Accepted Solutions
HP Recommended

Hi,

Most likely you need to replace the RTC battery and then set the correct configuration (date, time ...) in BIOS

The part number is 665733-001 (search online with part number)

Ex

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p4432023.m570.l1313&_nkw=665733-001&_sacat=0

If you can not find the correct part you can probably take to a local PC repair shop and they can insert a new 2032 button battery for a few $

On page 64 of service manual you can see the steps to remove the battery

https://h10032.www1.hp.com/ctg/Manual/c04655205.pdf

 

"The computer is slow"

Have you replaced the Hard Drive with a 2.5" SSD, this would give a great boost to performance.

Have you inserted 16GB of RAM

It is also an older notebook. 

 

Hope it helps,

David

Please click on yes for thanks
Please click on accept as solution if answered your question

 

View solution in original post

1 REPLY 1
HP Recommended

Hi,

Most likely you need to replace the RTC battery and then set the correct configuration (date, time ...) in BIOS

The part number is 665733-001 (search online with part number)

Ex

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p4432023.m570.l1313&_nkw=665733-001&_sacat=0

If you can not find the correct part you can probably take to a local PC repair shop and they can insert a new 2032 button battery for a few $

On page 64 of service manual you can see the steps to remove the battery

https://h10032.www1.hp.com/ctg/Manual/c04655205.pdf

 

"The computer is slow"

Have you replaced the Hard Drive with a 2.5" SSD, this would give a great boost to performance.

Have you inserted 16GB of RAM

It is also an older notebook. 

 

Hope it helps,

David

Please click on yes for thanks
Please click on accept as solution if answered your question

 

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