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CMOS error

My PC is dead, and the screen reads:

Found CDROM:
CMOS checksum error -- Defaults loaded CMOS battery failed

What's the problem with my PC?
You need to take your PC to a repair shop, or find a friend who is good at these things.

My guess is that there is a battery on your motherboard that needs to be replaced. Normally, these batteries last a few years, but there are functions, such as the clock, that require a battery to keep running properly, and when that battery dies, you replace it.

However, you didn't give me a lot of information -- like what make of computer it is, how old it is, what OS you're running, or even what kind of CPU it is. I'm guessing it's some sort of IBM-compatible something or other.

There are other things that could also be the problem. They include:
  • Your BIOS chip has gone bad.
  • One of your memory chips has gone bad.
  • Your CPU has gone bad.

    They're less likely, though. It's most likely just a simple battery, and if you want to, try replacing it yourself. Look for one on the motherboard, and get a replacement at a computer shop, Radio Shack or camera shop. If replacing the battery doesn't fix your problem, you *really* need someone who is an expert who can touch your machine.

  • This was last published in September 2001

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