trs96
Moderator
- Joined
- Jul 30, 2012
- Messages
- 25,535
- Motherboard
- Gigabyte B460M Aorus Pro
- CPU
- i5-10500
- Graphics
- RX 570
- Mac
- Mobile Phone
A Short Story about CMOS Batteries
My Optiplex MT was starting to have some issues so I thought I'd rule out the CMOS battery. I replaced it with a brand new Maxell CR2032 fresh out of a blister pack. I had bought it on Amazon a year or so ago. I usually even test new CR2032s with a multimeter but didn't bother as that wasn't anywhere nearby. The battery was brand new anyway.
I flashed the BIOS again and set it up as per the guide. It worked well for a few days, then the strange problems started again. The mouse would get laggy, it wouldn't boot normally and eventually I couldn't even get into the BIOS. Just a black screen, nothing else. For a minute I thought the BIOS was at fault. I took out the CMOS battery, left it out for 5 to 10 minutes with the power cord unplugged. Replaced the battery and tried to boot. Still no Dell Logo or ability to even enter the BIOS. Weird right ? Was this a board failure or what ?
Since I'd seen this before on my older 7010 Optiplex, I knew I had to replace even that "brand new" CR2032 battery. I was certain it wasn't software or EFI related. Sure enough, I put in a new Energizer brand battery and then everything started working normally. So why did the other Maxell battery not work ? My guess is that it was either defective or had just gotten too old even before I bought that pack of CR2032s. These coin cell batteries never have expiration dates on them. The truth is they don't last forever even if still in original packaging. Some Amazon sellers have them sitting around for many years before you buy them. So it's always best to buy from the bigger selllers like Amazon/Newegg rather than 3rd party sellers on their sites that may not have the freshest stock batteries.
If you go with Amazon Basics, you can be sure these get off the shelves rather quickly. The prices are low and people trust buying directly from Amazon rather than 3rd party sellers. These are what power AirTags from Apple so many more people will be buying these now. They only last for about 1 year in an AirTag. In your PC/Hackintosh they should last 5-6 years or more if the machine stays plugged into the wall outlet. I've seen some last for 8+ years.
https://www.amazon.com/dp/B0787K2XWZ/?tag=tonymacx86com-20
Make sure to buy fresh CMOS batteries and avoid problems like this with your Dell.
Last edited: