My laptop has been saying it was running low on battery, although it was hooked up to the AC…then the other day it completely died and would not turn back on (altho it was plugged in like usual) I called Dell, and the tech said that the motherboard is kaput and I have to replace it….but then yesterday, one week after talking to the Dell guy, my laptop turned back on, and so far, so good…so does this seem more like a battery issue (or am I just hoping for too much?) can I replace just the battery, or is there a built in battery on the motherboard? or is this just the beginning of the end?!