Resurrecting a Dead Computer

Last Update: September 20, 2015

I have an older desktop computer, and just lost a couple of days when it refused to boot up. It turns out that there's a tiny battery that desktops and laptops need to boot up. After five years or so, mine gave up the ghost - and my computer couldn't remember how to boot itself up anymore. Who knew?

Warning - geek talk ahead. Turn back now!


We've had some fairly hot weather recently, and my computer started randomly shutting itself off while I was working. I assumed it was the heat getting to it, so I opened the case, put a couple of fans nearby, and kept working.

We left the house briefly, and found the computer had shut itself off while we were gone. It was trying to reboot again - unsuccessfully.

Not good


I wondered what the problem might be. Possibilities included the computer's motherboard, its CPU, the graphics card, or the power supply - all pricey bits and pieces. <sigh>

I waded in, expecting the worst. I didn't find any blown capacitors or other indications of heat distress on the motherboard. All the fans within the computer seemed to be spinning, so I pulled the heat sink off the CPU to have a look. Mind you, there's not much to look at there, but I thought I'd clean the dust off the the heat sink and fan blades.

There wasn't that much dust on any of the fans, but I felt like I was doing something productive - even if all I was doing was rearranging the deck chairs on the Titanic.

I don't have the equipment to load test the power supply, so I just contented myself with making sure its fan was spinning when the computer was turned on. Check.

Reassemble, and cross your fingers


I tried booting the computer - without success. No real surprise there, since all I'd done was a bit of housekeeping within the case.

Suddenly, I had a revelation. There's a tiny battery in the computer called a CMOS battery. That battery's sole purpose is to preserve the computer's settings while it's turned off. Without that battery, the computer has no clue how to awaken. As luck would have it, I had one in my desk drawer, a CR 2032, a little Lithium button battery.

The bottom line? It cost me dearly in time, but could have been much worse financially. If your computer is misbehaving, consider replacing that 50 cent battery, and see if that fix works it's magic for you too!

Dennis

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SamiWilliams Premium
Dennis,
Thanks for this post. I have an older desk top as well- and you described it's symptoms. If I pop off the cover, will I be able to see where the battery is?
thanks
Shelly
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Prestones Premium
Hi Shelly!

What kind of computer do you have?

Try searching for:
replace cmos battery {make/model of your computer}

See if that does any good...

Dennis
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SamiWilliams Premium
Thanks I should have read farther before I commented.
Will see what hoppens,
Samo
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Freedomseekr Premium
Thanks for sharing Dennis! I wonder...my hubby's computer has been acting up instead of starting up correctly a lot lately (again) sigh...

Just maybe this could be the problem as it is getting up there in years...can't remember how old his computer is actually, lol!

I'll have to mention this to him and hopefully we can find that tiny battery in there...Thanks again and best wishes ;) -Sherry
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Prestones Premium
Greetings Sherry!

If you can't find the battery, you can always see if a search engine will help identify the guilty party's location ;)

Best of luck with it!

Dennis
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TopAchiever Premium
Excellent find and thank you for sharing! That is a good piece of information to know. Having done a bit of A+ I was aware that maybe replacing the battery would be the way to go.
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Prestones Premium
I've gotta ask Edu - what's A+?

... and what size battery does it take? :)

Dennis
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TopAchiever Premium
You are so funny Dennis. A+ is a IT Technicians Course designed to help you understand the hardware of a computer and how to maintain and fix it!

I guess it would come with a car battery or two if it was taught by a robot! :-)
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Prestones Premium
Hey Edu!

That explains it! My formal computer education consists of alternately breaking and fixing things.

I'm working on my PhD thesis now - How to Break the Internet ;)

Dennis
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Mark1957 Premium
Hey Dennis
You could have ended up binning your 'pooter for the sake of a 50c battery if you hadn't had that eureka moment so it's just as well you did!!
Mark
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Prestones Premium
Every once in a while you win one, right Mark? I just hope I haven't used up my quota for the rest of the year!

Dennis
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Quincy17677 Premium
I've known forever that there is a cmos battery but am not sure I'd ever be able to find where it is. Is is in a prominent location (hopefully)?
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Prestones Premium
Hello Willafay -

It seems each type of motherboard has its CMOS battery in a different location. If you can't find it with a cursory examination, the search engines can be your friend ;)

Dennis
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Quincy17677 Premium
Glad that you reminded me of search engines. I did refer to one when I could not unscrew a shower head and I learned that they screw in backward. That's a good idea. Thank you.
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adaba063 Premium
I do not yet have an issue with the cmos battery, my issue is with processor speed to too slow
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Prestones Premium
Hello Derrall!

If only there was the equivalent of coffee for processors! ;)

Dennis
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Ruthchicago Premium
very McGyver like, I'm impressed!
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Prestones Premium
Hi Ruth!

You have to remember that MacGyver was not only known for making repairs out of spare bits and pieces close at hand...

... he also occasionally blew things up with them!

Dennis
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billyadams Premium
Man, I love people who know what they're talking about!! Thanks!
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Prestones Premium
Greetings Billy!

It's all done with smoke and mirrors ;)

Dennis
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billyadams Premium
Sounds like a Lady Gaga song!
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Rodwell Premium
Great advice Dennis!
Tony
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Prestones Premium
Hi Tony!

If you upgrade your laptop / desktop every few years, you'll probably never see the problem.

Being the stubborn sun of a gun that I am, I just keep swapping out tired / obsolete components - and that silly little battery couldn't hold it together any longer ;)

Now I know...

Dennis
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Rodwell Premium
Mine are just starting to get a bit long in the tooth.
Tony
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Ken-Pringle Premium
Nice computer repair job Dennis.
If you charge by the hour, Ouch! ;-)
Nice share, thank you.
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Prestones Premium
Hey Ken!

Sometimes I'm my own worst enemy.

I decided to build my own computer in an oversize case, so I could swap out obsolete parts. The thought was that I could avoid buying an entirely new machine every few years.

That's the good news.

Unfortunately, there is no warranty for the entire system. What's more, some components are nearing 10 years old, and the service tech has been known to be a bit of an idiot from time to time... ;)

Dennis
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Ken-Pringle Premium
You got it to work that is what counts my friend.
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OldMCSEGuy Premium
Even before I was certified to work on computers, Ihad plenty of machines to have the cmos battery die. But I never had that stop a machine from booting... We learn something new everyday ... even after 40 years.
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Prestones Premium
Salut Keith & Jay!

Leave it to me to find the needle in the haystack! I suspect that the BIOS didn't know where to turn for a bootable disk, since the C: drive is a RAID array. I have a hard time doing anything normally ;)

The good news is that the computer has been well behaved now for more than 45 seconds!

<chuckle>

Dennis
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chengckalex Premium
If you can, blow the inside of the computer with air gun periodically. Dust build-up can drag the computer.
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Prestones Premium
Greetings Alex!

Sound advice - I think I was just going through the motions of cleaning out dust to keep my hands busy while my head was wondering "what next?"

Fortunately, there was a happy ending - this time ;)

Dennis
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Lazyblogger Premium
Thanks for that tip Dennis, you should name him Lazarus, lol. Thanks for the information. Will check one that I have.

Bishop
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Prestones Premium
Greetings Bishop ~

I've taken to calling the computer Poindexter (http://www.phrases.org.uk/bulletin_board/19/messages/498.html ;) but I'll have to give some consideration to your excellent suggestion, adding Lazarus as a middle name.

Dennis
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Lazyblogger Premium
lol
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AllMadeUp Premium
I feel like I've just learned one of life's great secrets! I am not kidding. This is awesome!
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Prestones Premium
Greetings Elizabeth!

It seems stupid to have a computer with 100 times the computing power used for the Apollo moon mission - but it's dependent on a IDBD (that's iddy biddy) battery to work.

Good Grief!!

Dennis
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AllMadeUp Premium
So tell me, is there a one-button way to share your blog on Facebook or do I need to copy and paste the link? I'm sure I have some friends who would love to know about this!
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allchristie Premium
Dennis - looks like I've been holding hundreds of these repair kits without knowing. Thanks. Larry
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Prestones Premium
Hi Larry!

I like the hat in your signature - I have one that's very similar. Sometimes it's a challenge getting close enough to the part to bring it into focus!

Dennis
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krazykat Premium
Hmmm. Thanks Dennis. Geek talk is often necessary :-)
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Prestones Premium
Thanks for your understanding Val!

When I open the computer, sometimes I feel like I'm just looking in the jumble of wires and printed circuits for a giant on-off switch or fuse to fix whatever ails it and bring it back to life.

Thankfully, this time I was able to sort it out before tearing out any hair!

Dennis
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