when pc is turned off and remains turned of on restart,even though a new battery is fitted

Hey easyways, do you get a CMOS Checksum error when you switch your PC on?

the pc in question belongs to someone else that i dont see often so dont know what errors he is getting,but wondered if anyone had got any ideas on it

The battery is the only thing, at least the only thing you can do to resolve this issue without replacing the board.

If the battery is not the correct voltage, or the battery has been used then it's not going to work. The battery he should be using is normally a 3v CR2032. If the voltage of the battery does not supply 3v then it's not going to work. If he has or can get hold of a multimeter to make sure that the battery is providing 3v.

If the battery is correct and providing the correct voltage, then this problem could be the battery connection onboard the motherboard, or a problem with the motherboard itself. Some motherboards provide a backup 2pin connection, next to the battery. The batteries for these can be ordered from here: Panasonic IBM P/N 02K6572, FRU P/N 02K6541 (CR2032-WR) IBM ThinkPad A20 Series, IBM ThinkPad A20m, IBM ThinkPad A20p Series, IBM ThinkPad A21 Series, IBM ThinkPad A21e Series, IBM ThinkPad A21m Series CMOS Battery.

Other than that, there is nothing he will be able to do except for replacing the motherboard itself.

This issue is caused when the CMOS values are incorrect. This issue can occur because of any of the below possibilities.

1. Bad or old CMOS battery.
2. BIOS update.
3. Disconnecting power from computer without shutting down computer

Attempt to reboot the computer. If error still occurs after rebooting the computer enter CMOS setup and check all values, this includes verifying the time and date are correct. Once everything has been verified and/or changed make sure you save and exit CMOS setup.

If the computer was had the power disconnected while it was still running it is possible this could cause the CMOS to become corrupt. Ensure that the computer is ready to be shut off before turning off the computer. If you have a laptop computer ensure that the battery is charged before disconnecting the power connection.

If you've recently ran a BIOS update on the computer the values stored in CMOS may have been reset. Enter CMOS setup and re-enter all the appropriate values.
If you're unable to enter the BIOS setup or after running a BIOS update your computer no longer keeps its values the incorrect BIOS update may have been installed for your computer or the version downloaded may be corrupt. We suggest trying to update the BIOS again and/or reverting back to an earlier version.

EDIT:Oooops sorry MM.

madmonkey

Jelly Bean

many thanks to you both very usefull info,

he did change the motherboard, but i was still interested as all knowledge is usefull.

Your welcome easyway will mark as answered.