This sounds like an issue with the motherboard or the hard disk. I think you've done all you could do yourself. If she didn't take extended warranty, I'm afraid you need a service tech. He will be able to tell what's wrong and how much repair will cost.
But first try the top post in http://forums.cnet.com/laptops-forums/laptop-troubleshooting-forum/?tag=contentMain;contentBody
It tells about the generic reset and the yearly maintenance against heat damage.
my girlfriend has had this dell inspiron 1545 for about a year and a half. it has always worked with out problems and has seemed to be adequate for her needs. that is until yesterday. she brought it to me and told me it would not turn on. I asked what she did to it and she insists that she has done nothing out of the ordinary (but who knows?). Regardless, the system does very little when pressing the power button. this is what I know 1)press the power button and the power/on white light on the front of the unit comes on and stays on solid white.
2)for an oh so brief time (a second or two, maybe) it faintly sounds as if the hard drive might be trying to spin, then nothing.
3)there is no display of any kind, ever. black screen upon powering up and black screen remains until powered off. therefore, if there are any error messages or if the screen would ordinarily say something at this point, I can not read it as the monitor is not working.
4)i can press random keys at random times and get various beeps and at one point it even played a brief melody of some sort. However, i can not specify which keys, the beep sequence or the melody. i can reconize that at some point after pressing keys i do reconize what i believe to be the windows goodbye sound.
this is what learned from various sites and what i have tried:
1)all the various post telling me to remove the battery etc....to discharge stored static, this does nothing.
2)removing the battery and trying to start using only AC power. again no help.
3)removing and reseating the memory cards, the hard drive and the battery, and nope still nothing.
i am hoping for the best here and want to avoid replacement or even the expense of taking it to a service tech, as with the economy being what it is we are broke, broke, broke. please help me if you can.....thanks!