Does the computer give a beep code or do the lights on the keyboard flash? If either of those is true, I think there would be a memory issue. But go through all the power and data connections on the inside of the computer, inc. hard drive, CD drive, motherboard, etc. If all those are connected and it still doesn't work, I am starting to think that the motherboard went bad. Go through that list and let me know if anything happens. Also look inside your computer for something out of the ordinary, like a blackened part of a component, or a damaged slot on your motherboard. The biggest thing is to check your I/O cards (PCI, etc.) for any that are sticking out. That could definitely be the problem causing a short circuit keeping it from working. Let me know if anything turns up.