My Computer Will Not Turn On
1. Ensure that everything is plugged in and turned on and that the computer console turns on before the monitor does.
2. Reset the BIOS (the operating system of the motherboard), by taking out the three volt battery, waiting for about 30 seconds, and then putting it in again. You could also reset the bios jumper on the motherboard instead of taking out the battery if your motherboard has a jumper for resetting the bios.
3. Ensure that no metal is touching the motherboard beneath it; except for the places for screws of course, and that the electricity outlet is working by plugging any device into it and seeing if it works.
4. Use a power supply calculator to ensure that your power supply can handle all of your computer components. Also ensure that the power supply is set to 115-120 volts (in North America), and 210-230
volts in Europe.
5. Take out any video cards, sound cards, USB cards, etc, and use integrated devices (the sound, video and USB ports already on the motherboard).
6. Ensure everything is in your computer that should be there (for example, make sure there is RAM, a power supply, hard drives, a motherboard, a CPU, etc).
7. Ensure all cords are tightly fitted (there are no loose power cords and/or transmission cables), and that the power switch on the front of the case isn't broken by checking that the wires leading from the motherboard to the computer switch are hooked up properly,(consult your motherboard manual for the correct configuration).
8. If you know how to protect computer devices from static electricity and are good with computers, take out just the motherboard with RAM, and the CPU. Hook up a hard drive and power supply and see if the computer works. If it does, there is a hardware conflict with some other devices that are in your computer. If it doesn't work, you most likely have a bad processor (1st most likely), bad power supply (2nd most likely), bad hard drive (3rd most likely as you would probably still be able to hear the hard drive clicking or something), or bad RAM (least likely as RAM is rarely shot unless you overclock your system).
9. The computer may be infected with a nasty virus (this is extremely unlikely however as something would still happen onscreen even if the computer was infected). Simply replace the hard drive if you feel this is the case and reset the bios. To recover info from an infected hard drive, put it into an external hard drive enclosure, plug it into your computer, and scan everything with a good anti-virus program. Afterwards, you can recover your files.
10. Perform a test of elimination. The power supply is probably shot, but to play it safe, swap hard drives and monitors to find the source of the problem. Also, wait a few minutes after turning your computer off and try again. This can ensure that your computer's capacitors are drained and you can turn on your computer again with a clean start. You should also try moving your computer slightly from any sources of interference, which may be preventing it from starting up.
11. Read your motherboard manual and/or consult a computer professional.
12. Good Luck!