I am about to replace the battery in my 8 year old laptop as the original one would only keep its charge for 20 minutes and has now died altogether. Hopefully that will restore the laptop to good health. But I was wondering how long a BIOS battery should last and what symptoms do you get when it runs down.

Same problems with mine to, similar age too. I think if your using mains power then take your battery out to extend its life, this was always too much hassle for me though lol

Sent from my Nexus 10 using Tapatalk

When the CMOS battery is flat then it will forget BIOS settings and the clock when all power is removed (including main Lithium battery).

Some machines will tell you that CMOS was reset, due to checksum error, that's usually caused by a flat battery if you didn't clear CMOS yourself.

 

CMOS batteris tend to be recharged from mains/main battery when the PC is on. Very very rarely do they fail (unless it's from HP...) Even on old laptops they can last for years. I can count on one hand how many I have replaced in my nearly 10 years of doing IT support. 

An 8 year old laptop is possibly on the cusp of the change over to rechargable ones. But as has been said, you get a checksum error, or a low voltage error when they are faulty. Or a not battery message when it is missing/caput.

Word of note. CMOS batteries in laptops are commonly in difficult to reach places and/or wrapped in sticky electrical tape. 

 

 

guess whos got an hp lappy,

guess who gets internal battery low.