I like to think I'm good at fixing things, especially electronics, but honestly I don't know nearly enough about much of anything. I don't know what the Kernels in a computer do, I don't know how the circuitry in the motherboard works, hell I don't even know how the master/slave chain works if you have more than one hard drive. But what I DO know is how to diagnose a problem. Anyone can "fix" the majority of problems they encounter if they approach it the right way.
Specificity is ImportantMy neighbors told me that the computer "wouldn't turn on" and that was basically all I had to go on before I was able to physically see the machine. This is the first reason people have trouble fixing things. They don't really know what problems they are experiencing. If a computer "won't turn on" that might mean that when you push the power button absolutely nothing happens. It might mean that when you press the power button it lights up and then instantly dies. It could even mean that the computer technically powers up but nothing happens on the screen if they are not being specific.
Each one of these scenarios means very different things and if you do not differentiate between them you won't get very far in fixing your problems.
In this particular case the computer would power up if you hit the power button and the lights in the button would light up but then everything would turn off.
Determine What You Already Know
Work Your Way In
Think of the computer as a circuit of information, or a chain of events. Pressing the power button -> Activates power supply -> Processor turns on -> Activates CD drive -> etc. In that scenario if the power supply and power button work and the CD drive does not function as it should (and you have no reason to suspect the CD drive is broken!) then the only missing link is the processor. Now, when i say "the processor" i mean the cpu, the ram, the video card, the sound card, the network card, the motherboard, all that junk. that may be a bit beyond the average user and actually fixing most of it is beyond my skills, but determining that the problem is there might save whoever you actually pay to fix it time trying to look for the problem. What is important is the process of determining information.
Now Put it to Use
Does it work now? Yup, it was just drained.