New to Ubuntu: "Non-System disk or disk error, replace and strike any key when ready"

OK, I took the plunge and installed Ubuntu 9.04 on an older (circa 2003) laptop Compaq Evo N610c.

Things were going well, then I discovered this strange issue: when I turn it on after it has been shut down and the AC power unplugged for more than a few seconds, I get this message "Non-System disk or disk error, replace and strike any key when ready"

Please note:
-The battery does not hold a charge, so I leave it removed to lighten the load.
-If I leave the lappy plugged in to the AC power, it boots up Ubuntu just fine.
-If I unplug the AC power for just a few seconds then plug it back in Ubuntu boots up fine, but if I leave it unplugged for more than just a few seconds I get the error message when I plug the AC back in and reboot.
-The only way in my limited knowledge to get operational again has been to do a full reinstall of Ubuntu each time.

Might this have anything to do with the button-cell ("wristwatch") battery? As far as I know it has never been replaced.

Or BIOS settings perhaps?

 

Do you have a floppy or CD in your drives that you forgot to remove?

 

Nope. No CD or floppy in their drives.

 

My first thoughts are that it sounds like your hard drive is going south, only responding properly periodically. Make sure that it's plugged in properly, and if so, you're probably looking at getting a new drive.

Laptops don't have "button cell" batteries like in desktops. They use their regular batteries for that purpose, so when you removed it, you lose that backup. Does the same thing happen without the battery plugged in? What happens if you turn the laptop off for an extended period of time, but leave it plugged in... does it start back up alright?

 

It could be something to do with the CMOS battery being dead, so your boot settings wouldn't show up without AC. That would force you to go into the BIOS Setup (or boot menu) each time you turn it on. It would also make sense that reinstalling would "work", because you'd boot from removable media by default.

 

Probably not -- there's never a problem booting with AC power.

There are CMOS batteries in laptops... they're usually the same CR2032 used in desktops. They do not use their regular batteries to store BIOS settings.

 

Out of curiosity, what happens if you leave the battery in? Also, when does this error show up? Can you get to GRUB bootloader, or to the BIOS?

Cheers...

Edit: Ninja'd!

 

IMHO, it most definetly sounds like a dead CMOS battery. Does your floppy work? My suspicion is that it doesn't work properly either. As long as the power isn't interupted, the CMOS holds its settings (probably with the hard drive before the floppy in the boot order), so it doesn't matter that the floppy is on the fritz. Since the settings are lost whenever the power source is removed, the CMOS reverts to default settings which probably includes placing the floppy first in the boot order.

Replace the CMOS battery, find a replacement main battery, or plug the laptop into a UPS and never unplug it.