One thing I would suggest doing, take the power cord out of the back of computer, press the catch on the plug and pull out the main power plug going to the board, place back in and make sure it is well down (seated correctly), if its near the edge of the board the power socket place something under the edge to support it when pressing the plug in, plastic or a small block of wood will do, if you cant find anything cut a credit card up into small squares and place on top of each other till you fill the gap, this is only to stop the board from damage as they are fragile and could bend and touch the case, and with battery on board you never can say what may happen if it shorted out with case.
EDIT
Read your posts again found no mention of the OS if its XP then carry on its not what I was thinking the problem could have been.
Jim
EDIT
Read your posts again found no mention of the OS if its XP then carry on its not what I was thinking the problem could have been.
Jim