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Resolved Question

Computer has CMOS error from being unplugged

Sep 9, 2016 2:10PM PDT

First of all, I am not a computer savvy person. I can operate Windows but that's about it, I have no experience dealing with advanced hardware and software issues, and I'm afraid to lest I break something. I only made a Cnet account so I could ask this question.

I went to turn on my Acer desktop computer (running Windows 7) today to find that it had accidentally been unplugged. Now, when this usually happens, I turn it on and find that the clock hasn't been keeping time without power, and is is displaying the time it was when the computer was unplugged.

With a Google search and some basic reasoning, I deduced that the battery inside of the CPU responsible for keeping time when no power source is present had died. I didn't think this was much of a problem, since I could just keep my computer plugged in all the time and manually set the clock if the power ever goes out.

That was about a year ago. There have been power outages and nothing bad ever happened.

Today I turned on the computer after it had been unplugged all day. I was met with an extremely laboured and overworked cooling fan, three beeps, and an error message filled with technical specifications that said "CMOS Checksum Bad". It also said something along the lines of "Date / Time not set", but I cannot remember it word for word, since after I tried turning the computer on and off, that line no longer appeared in the error message. Now, when I press the power button, the computer won't shut off, only restart. I can only assume the aforementioned dead CPU battery is the cause of this, but if so, then why didn't this error happen until NOW?

The screen is giving me the options to "Press Del to run SETUP" or "Press F1 to load default settings and continue".

Please tell me, what is going on here, and which one should I pick? I was going to press F1, until I read up and realised that this battery also controls other functions, such as the virtual size of the hard disk. I have a lot of files with sentimental value on that computer, and I imagine the effects of having the hard drive designated as smaller than the amount of data stored on it would be... unfavourable. I also saw someone on a forum who said he lost all his files as a result of doing this, although his circumstances are no doubt different from mine.

I'm tempted to unplug the computer so that its abnormally laboured cooling fan doesn't wear itself out, but considering that this entire issue was caused by the thing being unplugged, I'm not so sure that's a good idea.

Also, in case this is useful, the logo at the top of the error screen reads "American Megatrends", which is strange considering the fact that this computer was manufactured by Acer.

Thank you.

Discussion is locked

A-Person-on-the-Internet has chosen the best answer to their question. View answer
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Clarification Request
Thank you for the responses.
Sep 9, 2016 2:47PM PDT

So, are you saying I should simply press F1 and restore default settings, then? What settings can I expect to lose, and what effects might that have? Will my files be affected in any way?

I did decide to unplug the computer to shut it off at the insistence of a friend. Could this have worsened the problem? Why was the computer refusing to shut off after doing it once?

This computer is important and vital to my daily work, but I am in no way qualified to open it up and replace its parts; I would probably end up breaking something. Would I be able to continue using the computer as if nothing had happened so long as I keep it plugged in at all times? Would I continue to get that error message if it has a constant alternating current to keep the CPU alive?

Finally, and this is purely out of curiosity, why was the cooling fan revving so intensely while the error screen was displayed?

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Sadly
Sep 9, 2016 3:23PM PDT

Since this is your PC only you know the right settings. If the defaults work, then go with that, if not your PC, your choices on settings.

As to AC, you have to test this.

As to worsened, the battery is old and given such a cheap part I can't guess why you don't replace it.

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F1 did nothing.
Sep 9, 2016 3:41PM PDT

Don't misunderstand, I want to replace the battery, but I don't have the skills necessary to safely remove the computer's case and replace a small, obscure component without messing something up.

But... I know that's my problem, not yours. So forget it.

I tried pressing F1 as instructed, but it did nothing. The error screen just stayed there as though the computer was frozen. I'm not sure if there's anything that can be done about that.

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If F1 doesn't work, it could be one of those older PCs.
Sep 9, 2016 3:48PM PDT

I have one last desktop from a decade ago. If the BIOS settings are lost I have to go get a PS/2 keyboard. The USB keyboard only works after the BIOS is changed and can't be changed with the USB keyboard.

For some this may mean the end of this PC. That is, the cost of the repair counter here is 150USD minimum. For something trivial at the shop.

Here's a youtube on changing the usual battery.


It's not that fragile.

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Thank you.
Sep 9, 2016 4:06PM PDT

Ah! It just so happens I have a PS/2 keyboard lying around nearby.

The computer isn't THAT old, it's like 9 centimetres (3 inches) thick and it runs Windows 7, but I'll give it a shot.

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Battery
Sep 9, 2016 3:53PM PDT

If you don't feel confident to replace the battery ask your friend or neighbor to do it.
Remove the old battery and take it to your local merchant and buy a new one.
Install the new battery.
Enter the bios and adjust the settings.

After you get the machine working I strongly suggest you make a backup of these files you don't want to lose.

Best Answer

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The battery got worse.
Sep 9, 2016 2:15PM PDT

Before it was too low for the clock to work. Now it's too low to retain settings.

NOTHING IS WRONG HERE. That is nothing unexpected. The battery if it's the usual CR2032 costs us about 1 dollar. If the machine isn't worth that, continue what you are doing.

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Answer
battery is dead
Sep 9, 2016 2:30PM PDT

replace the motherboard battery. also remember acer may have built the computer, all the parts inside of it was built by other companies.