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- What RTC (BIOS) battery is used in HP Probook 4540s and when...

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01-28-2017 09:42 AM
Hi there! Let me know what RTC (or BIOS, CMOS) battery is used in HP Probook 4540s? Your service guide doesn't tell it.
My notebook is at least 3 years, I don't have any problems at the moment - but it would be good to know when should I replace it?
Thank you
01-28-2017 09:51 AM
01-28-2017 10:11 AM
Sorry, but I wanted to know what battery type is used there? I know it's a button cell battery, but which one (CR 2025, CR 2032 or other?)
Wouldn't it be cheaper to just buy a new battery instead of buying a whole spare part with those 2 cables?
01-28-2017 10:55 AM - edited 01-28-2017 11:26 AM
My company refurbishes 7-10 thousand laptops per month.
Most are Dell, HP and IBM's.
The HP's we process most are the ProBooks and EliteBooks.
Many are much older than yours and we rarely need to replace the BIOS/RTC battery.
The exact Born on Date of your laptop can be calculated by your Serial Number.
XXXYWWXXXX
Y = YEAR
WW = WEEK
REO