It would have nothing to do with the "modem" (unless that is where the lightning got in over the phone line). People somtimes think the tower case is called "the modem" so that may be what your friend ment. It is one of two things. Your power supply is blown out or your motherboard is fried (maybe along with the power supply). If you are ok with poking around inside the computer you can do a test.. or you can just take the whole thing to a computer repair shop.
Testing is safe in as far as all the electrical parts inside a computer tower case run on DC voltage (as long as you dont open up the Power Supply... its the big metal box inside with all the wires coming out of it) Everything else in there can't hurt you, but you could blow out something that is not already fried if you connect something wrong. When unpluging wires make sure computer is unpluged from the wall AC outlet... it is always on if it is pluged into wall and you could fry something.
If your tower case is a standard ATX style case (Dell Dimension 3000 may or may not be) you can buy a replacement power supply for $30-$40. Swapping it in (lots of wires to uplug/plug) could be a quick cheap fix. You can even test the old power supply by unpluging it from the motherboard and, using a piece of wire you can short the pin 14 on the connector to pin 15. If it is ok the the power supply fans will spin. If the PS is ok then the motherboard is dead.
You could replace the power supply and motherboard by buying what is called a "bare bones" case (see any online retailer). Such a case will come with a new tower case, Motherboard, power supply, and even a CPU and RAM on it. All you would do then is swap all the other parts including the hard drive into it (all your software should run but this may intail a call to Micrsoft to re-setup your Windows XP serial #).
Robbie
July 2007
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