PCMechanic has posted a guide about troubleshooting your computer

If you're going to be building computers, adding devices to your computer, altering BIOS settings, or just installing and deleting programs on your computer, then you'll want to learn the basics of troubleshooting. You might notice that I didn't say computer troubleshooting. That is because troubleshooting is an independent skill. I learned to troubleshoot as an electronic technician. And most of those same techniques work fine for troubleshooting computers.

Troubleshooting is really a kind of detective work. If you notice, the TV detectives spend a lot of time asking questions and thinking over the facts. And that is where a good troubleshooter starts, asking questions, not with tearing apart their computer, swapping components, or running diagnostics programs.

Read more