CMOS battery dead/dying - so?

zhen_rogue

I have a notebook computer that's about 4 years old.
When I completely disconnect the unit from AC power, the system clock stops keeping time.
When the unit is connected to AC power, everything is fine.

A bit of research tells me that the motherboard CMOS battery is dying or dead.

The question is, besides keeping accurate system time (which honestly is no big deal, as my computer is off AC power about 1% of the time), what other potential problems will a dead CMOS battery bring?
I've already investigated changing it myself, and my notebook uses some form of custom housing for the battery - meaning i'd likely have to send the unit off for a repair, which means $$$ and a couple weeks with no system.

Thanks for any clarification.

Spudge

What model of laptop do you have? Generally "custom battery housing" just means an external battery pack connected to the mobo by leads instead of a battery seated physically on the board. These are fairly easy to replace and replacement parts can be had cheap

(also I'm a seasoned HW tech just a few miles from you - If you got the part I'd swap it for you if you didn't feel confident enough to do it yourself)

runethomas

yeah what type of laptop do you have?

maybe this page could help out some.

http://www.laptopparts101.com/cmos-rtc-battery/

zhen_rogue

I have a Sager NP5760.

Spudge

Righto. The CMOS battery is (looks to me like) a standard CR2032 button battery, wrapped in a fancy piece of plastic with 2 wires and a 2-pin Molex

Wouldn't be hard to replace, just 10 or so small screws and probably an hour or so

zhen_rogue

What does the CMOS battery do for me, other than keep time when the system is sans AC power?
I've read that most notebooks don't lose BIOS codes etc. when the CMOS dies, so surely it has some other purpose beyond time-keeping?

If time keeping is all it is, I won't worry about it, as this system is basically never without AC power.

Spudge

That's pretty much the gist of it

Though I have heard of some Windows programs using the RTC for licensing, so there's an off chance you may run into that

Tofystedeth

If you're not losing your BIOS settings when you cut power you probably won't notice much problem, as long as your clock is getting corrected before you try and go do stuff. A badly wrong system clock will prevent you from accessing secure websites, or sending email via SSL.