A hardware question

We retired a perfectly good Acer desktop about six months ago and it hasn't been booted in that time. Previously it has had a 100% reliability record. A friend has a use for it so today I powered it up with the intention of cleaning it up for a new user, but only the fans are powering up - no disk activity lights, no screen output, no power to USB.

I'm wondering if a completely flat CMOS battery could be the cause? It has never been replaced, and when the machine was in daily use it was being kept charged. It fits the facts but I just don't know enough about hardware to know whether this could be the cause. I hope it's that simple as it's a nice machine.

 

The CMOS batteries are inexpensive and since it's never been replaced, it may be a good idea to do so. If the computer powers up afterward, you'll have your answer. If it doesn't, at least it will be one less thing the new user need be concerned about after anything else is sorted out.

 

Well personally, not that I know the first thing about the role of CMOS batteries in bootup, I'm a bit dubious as to whether a flat battery could cause a complete loss of power to everything other than fans, and I was hoping that someone who does know something about these things might be able to save me the hassle of having to get and fit a replacement by confirming that it wouldn't be possible. I'll leave it plugged in for 24 hours - maybe that will revive it.

 

In an old computer we have that needs the CMOS battery replaced, when it is powered up, it says "press F1 to load defaults or press F2 to enter setup". Windows still loads. (I'm scared to replace the CMOS battery because it is an all-in-one computer and I have to pry the back off the LCD to get to the heart of the computer. I'm afraid I'll break the plastic clips and never get the unit back together. We'll run it as is until something else goes. We've been using this free, 2nd hand unit since 2006).
I doubt whether the symptoms you describe can be attributed to a dead/flat CMOS battery.

Do you have a spare power supply to try? The PSU might be on it's last legs with only enough power to run the fans.

Another thing to look at: open it up, reseat the RAM and be sure all the wires are tight.

 

Earthling, CMOS batteries are not charged by the computer. Maybe on newer PCs. Replace it. It's a CR2032 and cost about $1.

 

It's nothing to do with cost, but if a dead battery could not be the cause of this situation then I wanted to avoid the pointless hassle associated with obtaining and fitting a new one when it wasn't going to cure the problem. But I needed to resolve this so both friend and I can move on. So I got a new battery and the old box booted up just like new

 

Amazing what that relatively unknown item can cause.

Good to know the PC is working. :celebrate

 

I'm glad it WAS that simple.

 

Computers still continue to amaze me. I would never have guessed a dead/flat CMOS battery would cause a computer to only run fans and nothing else.

 

Me neither plodr, but it seems a PSU needs a battery to get going! :-D

 

Maybe yours does. I just read a post within the past week at one of the forums I look in at where the owner forgot to put the CMOS battery in. He fired up the PC with no problem then noticed the CMOS battery sitting on the computer desk. So, all hardware does not act the same.