I though you were going to say it was an inspiron 1501 somehow!
It seems to be a common problem with them, and from all the forums about it even Dell seem to be unable to offer a 100% solution.
some people with this problem have said that updating the system BIOS to the latest version solves it
http://support.dell.c...atid=-1&fileid=230865
But then other posts I've read say it doesn't help and a new motherboard was the only cure.
You can try updating the BIOS, do it very carefully and follow the instructions on the link above to the letter, if something goes wrong while updating the BIOS it could render the laptop unusable!