CMOS Battery
Thread Starter

Joined: Jun 2009
Posts: 1,344
Likes: 80
From: Bedford, UK
CMOS Battery
Lifetime event: I replaced the motherboard cmos battery in an ancient PC (2010) after it became troublesome and in the end wouldn't boot. That's a lifetime first. The fact that the bios lost date and time a week or so back was the clue. Apparently the advice is to replace them every 5 years but I am not made of money.
However, in addition to now booting, the whole machine seems sharper and more responsive somehow. So to those with old machines perhaps change the battery ?
However, in addition to now booting, the whole machine seems sharper and more responsive somehow. So to those with old machines perhaps change the battery ?


Joined: Jan 2008
Posts: 315
Likes: 57
From: LONDON
Lifetime event: I replaced the motherboard cmos battery in an ancient PC (2010) after it became troublesome and in the end wouldn't boot. That's a lifetime first. The fact that the bios lost date and time a week or so back was the clue. Apparently the advice is to replace them every 5 years but I am not made of money.
However, in addition to now booting, the whole machine seems sharper and more responsive somehow. So to those with old machines perhaps change the battery ?
However, in addition to now booting, the whole machine seems sharper and more responsive somehow. So to those with old machines perhaps change the battery ?
Thread Starter

Joined: Jun 2009
Posts: 1,344
Likes: 80
From: Bedford, UK
Gnome de PPRuNe



Joined: Jan 2002
Aviation Qualifications: Spotter
Posts: 15,197
Likes: 1,201
From: Too close to Croydon for comfort
Had an intermittent fault on an old Lenovo laptop which prevented it from booting up properly. The remedy, prescribed by YouTube, was to remove the battery pack AND the CMOS battery for 20 mins until all residual power had ebbed from the circuits, reassemble and away it would go.
Ah the days when removing the battery was simply pull back a couple of clips and to get to the innards undo a few screws. Now you need a combination crowbar, tin opener and acetylene torch and in all liklihood something will crack as you pry...
Ah the days when removing the battery was simply pull back a couple of clips and to get to the innards undo a few screws. Now you need a combination crowbar, tin opener and acetylene torch and in all liklihood something will crack as you pry...





