Error 0251: System CMOS checksum bad - Default configuration used

[joe]

Go this problem on my laptop, it wont boot up now. I've read elsewhere that this is a CMOS battery problem. However, the clock hasn't slowed down and when I tested the battery (i think it's the right one-it looks like a large watch battery) it was fine.

Has anyone got any ideas? The laptop is a Twinhead, quite old PII, running XP.

[ALG]

its the battery m8, replace and do a bios reset and it will be fine, even a .1 voltage drop can cause a bios error.

PS you wont get a PC clock to 'slow down', it doesnt work like that :)

[Dave Mak]

could be a dying battery, or your cmos chip has become corrupt. try going into the bios and "load system default settings" option or something similar.

IMPORTANT!!!

if you do reset back to system defaults, get a digital camera and take a photo of every bios screen BEFORE you reset to defaults, that way if it makes no difference, you have a visual reference of all the settings :ok

[SKUNK1111]

or use a phone to take the pics mate. :)

[joe]

cheers guys thanks for your input. I took it to a shop last week to get a new battery. The guy in the shop said that the old one i gave him was ok (still had 3v he said), so i didn't get a new one.
BUT i trust you lot more, so i will get a new battery if ressing the bios doesn't help.
Thanks

[joe]

I've set the bios to default settings and put a new battery in. I still get the same error. I'm gonna try and re-flash the bios tonight hopefully-if I can find it.
Any other suggests please?

[ImCal]

_http://www.smartcomputing.com/techsupport/detail.aspx?guid=&ErrorID=26143

[joe]

Cheers Imcal, but it seems their advice is also to try a new battery! btw i notice that the clock hasn't lost any time even tho i've taken the battery out.

[thetarget]

when you reset the bios by removing the cmos battery the bios time/date should go back to dafault if it never done this i would say it never reset the bios


leave the battery out over night would be a sure way to do it (making sure it has no power coming from the wall lol)
or find your motherboard cmos reset jumper

lol i just worked out its a laptop lol make sure you also take the main battery out too

[joe]

Cheers Target, I thought that it was a bit strange that the time did not reset. I will try overnight tonight.
Something elese interesting that might give someone a clue what is wrong:
The laptop seems to boot fine with no CMOS error IF I disconnect the power cable first. Is this strange or am I missing something? Any ideas welcome, at least I 've got a tempoary way of getting it booted up.

[joe]

I left the cmos battery and laptop battery out over night, this has made the time reset (and so probably the bios). But nothing else has changed unfortunatly.
I'm trying ultimate boot cd but i can't get it to boot from here either. I've changed the boot order in the bios but it not working.
Has anyone got any other suggestions please? I want to chuck it out da window