Hey all,

I'm having a terrible problem.. my old Mobo died so I had to upgrade to a Gigabyte GA-7N400 Pro2 with a Athlon XP 2600+ processor, and 512 crucial ram and a 9200 ATI card. I've assembled all the parts and it boots up, but I get the following error:

CMOS checksum error - defaults loaded

However, I can't press any buttons to get into the BIOS to fix this, for some reason it freezes and the only key on the keyboard that responds is the numlock key. I've tried replacing the battery several times, and the same error comes up.. anyone know how to fix this?

It may have something to do with xp already bieng on your hd?

Do a search on here to find out more.

nf7-s v2.0
1gb pc3200
jou jye 550w psu
xp2500-m @ 200x11
Thermalright SP 97
fx5600@360&600
WDCaviar 60gb
Seagate Barracuda 80gb
Thermaltake Lanfire

;~}

I've done searches on here about it. All the people say that their keyboards don't work after CMOS checksum error - loading defaults but there's never a response after that. Maybe a USB keyboard would work? I don't know..

No,No,No you misunderstand(I don't explain very well also).

I presume you are using your old Hardrive?
Windows xp does not like bieng swapped to new systems.

i.e A new mobo change

Also checksum errors can occur with dead/dying mobo batteries but you already eliminated this option.

nf7-s v2.0
1gb pc3200
jou jye 550w psu
xp2500-m @ 200x11
Thermalright SP 97
fx5600@360&600
WDCaviar 60gb
Seagate Barracuda 80gb
Thermaltake Lanfire

;~}

Nothing to do with what is on the disk. When a CMOS checksum error occurs, the BIOS hasn't even looked at that hard disk.

Try resetting the CMOS memory. You motherboard manual will tell you how to do that. You will still get a CMOS check sum error but you should then be able to get into the BIOS setup screen to set the necessary parameters. You motherboard manual should tell you what key or key combination to press.

Stuart

ok

My misunderstanding

nf7-s v2.0
1gb pc3200
jou jye 550w psu
xp2500-m @ 200x11
Thermalright SP 97
fx5600@360&600
WDCaviar 60gb
Seagate Barracuda 80gb
Thermaltake Lanfire

;~}

Thanks for the advice guys... I've tried resetting my CMOS by the CLR_CMOS jumper, and also switched out the battery for the working battery (both +3V) and no change.. I think if I can get the keyboard working the machine will be fine, any ideas why the keyboard would not function, 'cept for the numlock key turning on and off when I press it?

Try pressing F8 or Del furiously on boot up?

nf7-s v2.0
1gb pc3200
jou jye 550w psu
xp2500-m @ 200x11
Thermalright SP 97
fx5600@360&600
WDCaviar 60gb
Seagate Barracuda 80gb
Thermaltake Lanfire

;~}

I think the main problem is the cmos error. I guees there's chance that you could have a defective cmos chip. Acyually, these days the cmos chip is actually built into the Bios chip.

I don't think that will work, but I'll try it anyway.. it's a very small amount of time from the button press until this screen, do you think this may be related to the FSB or the clock ratio?

"Acyually[sic], these days the cmos chip is actually built into the Bios chip."
-The CMOS (Copper Metal-Oxide Semiconductor) is the name of the chip (or, to be more precise, the type of chip) that contains the BIOS.

"Try pressing F8 or Del furiously on boot up?"
-Those buttons are for Windows - from what it sounds like, the computer is freezing before or during the POST, so (as Stuart mentioned) Windows doesn't even get the chance to boot up. Pressing these buttons would have no effect (unless the unlikely event that one of these buttons happens to be the setup key, but that key is more likely insert or F1).

"do you think this may be related to the FSB or the clock ratio?"
-It doesn't matter if you can't get into your BIOS...

If, as you say, it's not the CMOS battery, and clearing the CMOS helps nothing, and you truly can't get into the BIOS, then I would contact your motherboard manufacturer while your warrenty is still good.

>> The CMOS (Copper Metal-Oxide Semiconductor) is the name of the chip (or, to be more precise, the type of chip) that contains the BIOS. <<

Actually CMOS (Complementary Metal Oxide Semiconductor) memory is volatile, that why it needs a battery. The BIOS code isn't and it is stored in non-volatile memory, ususal flash memory these days. But as ham30 says, they are often built into the same chip these days, along with the RTC and the keyboard controller which used to come on seperate chips. Most BIOS chips only have 64 or 128 bytes of CMOS memory and 256KBs of BIOS memory.

If resetting the CMOS does nothing its looking increasing likely like a duff keyboard or a duff BIOS chip. Try another keyboard first, they are cheap enough and its always handy to have a spare in case you spill coffee all over one.

Stuart

I've tried two PS/2 Keyboards, I'm going to try a USB keyboard tonight and then if not I'm going to call Gigabyte.

Heres a useful site for the lowdown on BIOS

http://www.pcguide.com/ref/mbsys/bios/comp_CMOS.htm

http://www.pcguide.com/ref/mbsys/res/pnpESCD-c.html

Thanks everyone! I tried again last night and it worked.. apparently I was shorting out the keyboard plug somewhere, thanks again!

Great! Its often something simple like that can cause the most exasperating problems.

I take it now that you can get into the BIOS setup screen and save the information which will eliminate the CMOS Checksum Error.

Stuart

sir,
i am also having problem with the same message "CMOS checksum error -default loaded". But the system does not freeze after showing the message. Instead, it gives other message "enabling swap space" after giving the login and password.

Mitali Pandey
project associate