View Full Version : CMOS Checksum Error - Defaults Loaded

10-28-2005, 10:22 PM
I get the message:

CMOS Checksum Error - Defaults Loaded

when i startup my PC. Is this something that can be fixed easily?

I can give a more detailed description of this problem:

I have built up a PC from scratch. Everything else works, except from the Floppy Drive (3 1/2).

I have tested this floppy in another working PC and it works 100% OK.

I have also tested the cable, it works too in the working PC.

wileya mentioned jumper settings. this is interesting because I had to change jumper settings for the CMOS as there was a sticker on the motherboard that said change jumper settings as they are set to clear.

I cahnged them to normal, but i think there seems to be something strange somewhere.

the motherboard ( and battery are brand new!). when i start the pc into windows the time in the bottom right-hand corner starts at 00:00 every time???

any help greatly appreciated


10-28-2005, 10:42 PM
Well if the motherboard can not remember what BIOS/CMOS settings have been set and is loading the defaults every time it starts, as long with the clock being reset then the CMOS battery needs replacing. Even though the battery is supplied with a brand new motherboard, there are still times when they are weak on arrival and need replacing. Also the CMOS jumper should be set to "normal" and not "reset/clear" for normal operation. Normal operation is usually between pins 1 and 2, with the reset being 2 and 3.

10-28-2005, 11:44 PM
Also the CMOS jumper should be set to "normal" and not "reset/clear" for normal operation. Normal operation is usually between pins 1 and 2, with the reset being 2 and 3.

Check your manual to make sure you set it to the correct pins. Maybe you didn't put the jumper on all the way when you changed it and its not connecting the battery.

10-29-2005, 12:52 AM
hi weazel and oracleguy,

thanks for your help.

other than a battery replacement and checking the jumper settings are there anything else you would recommend?

would I be able to take the jumper OFF completely without causing any permanent damage?

i have tried googling this, but not having much success???

the cable is working and is connected in the correct way. the drive DEFO works. what else can it be?



10-29-2005, 12:57 AM
You wouldn't cause any damage by removing the CMOS jumper. For normal use and operation it has to be in the "normal" position. I would have thought that if the jumper is removed then the system won't POST or boot - usually if you put the CMOS jumper into "reset" mode and try and start the system up when you press the power button nothing will happen until you put the jumper back in it's "normal" location.

Anyway, if the board has been supplied with a dodgy battery then it the motherboard manurfacturer are liable to replace it, however if it is a dud then go out and buy a new one - I got a few for 1 each.

10-29-2005, 06:48 PM
have been working on this further and now it seems when there is ANY error on boot up then it resets the CMOS and wont allow the floppy drive to work.

For example, i started the machine up without a keyboard and mouse and it gave me "No Keyboard/Mouse present" as well as "CMOS Checksum error - Defaults Loaded".

Then when i press F1 to continue it boots up into Windows fine, but the clock is reset and the floppy doesnt work??

I am going to purchase a brand new battery and try it. But surely if I make a mistake such as no keyboard/mouse then it shouldnt reset the CMOS???

The jumper settings for the CMOS are in the correct position. On the motherboard it states;

There are three pins and the jumper is covering pins 1 and 2.

Has anyone got any input or ideas?

They would b much appreciated. Contact or any tips by SMS on 07811574203 would be handy!



10-30-2005, 01:28 AM
The jumper should be set to normal. If it's resetting the CMOS everytime there is a POST error, I don't know if there is a setting in the BIOS that does this, but to me it sounds like the board is faulty.


10-31-2005, 03:30 PM
could this be something to do with my RAM? CPU?


10-31-2005, 04:36 PM
Unlikely IMO...more to do be a problem with the motherboards inability to save BIOS information properly. A BIOS upgrade might solve it I guess.

10-31-2005, 07:04 PM
It is definetly a problem with the motherboard and not the CPU or RAM. What make and model is the board?

10-31-2005, 10:34 PM
Get a decent Asus, MSI or Gigabyte board IMO..don't waste your money on stuff like PC Chips.