Rtc battery

[Lexie77]

Does this laptop have cmos battery?

Because after discharging New battery with callibration then charging the battery for 4 hours when turn on the laptop appears bios checksum error.

So the New battery always ask for callibration, already trying callibration with 2 New batteries. 

Pls help, thanks

[Paul_Tikkanen · Accepted solution]

Hi:

Below is the link to the service manual for your notebook.

If you look at chapters 3 and 6 you will not find any references to a RTC/CMOS battery, so your notebook does not have a separate RTC/CMOS battery.

The main battery serves as the CMOS battery and since you have already tried to calibrate two new batteries, I suspect there is something seriously wrong that would require a motherboard replacement, or you are buying the wrong battery.

Unfortunately, I wouldn't be able to help you figure out what the actual problem is.

The battery part number and description can be found in chapter 3 of the service manual.

[Lexie77]

Thank you

[Johnharper241]

All computers, including desktops and laptops, have a small battery inside the motherboard that provides power to the CMOS (Complementary Metal Oxide Semiconductor). This battery is known as a CMOS battery.

[Paul_Tikkanen]

You're very welcome, @Lexie77 

@Johnharper241 this model notebook does not have a RTC battery as is shown in the service manual.

There is no RTC battery part number and no procedure to remove or replace a RTC battery.

That is the case for almost every HP notebook that comes with an internal battery.

You have to read the service manual in order to answer the question.

If you do not read the service manual, then you cannot provide an accurate answer.