Fixing time error

Question

I have a hp dv7 series 3050 laptop.

Recently, I left it on charging on standy mode and someone unwillingly disconnected the charger and it turned off.

At the restart I noticed that the time was strange, every time when it reach 4pm, it automatically goes back to 3am, the same thing when I start it.

After brief research, I saw that it has a problem with the cellboard, responsible for maintaining the BIOS settings even after shutdown.

The BIOS model is F.1b. I'd like to know a more professional take on what may be happening, and what should I do to fix it.

Answer 1

You probably need to replace the battery that keeps the real-time clock powered.

This picture is of an HP dv7 model with the bottom cover removed. Image by Mark

You can see the circular battery on the mid-right, and it looks like a standard CR2032 lithium button battery which is available just about anywhere. You can often find it in stores because it's used in many other things like watches, which is why many people call it a watch battery.