Rules of thumb when troubleshooting computers

[aimeeandbeatles]

One of my main rules of thumb is to never troubleshoot one when I'm tired. I always just get it to a working state, go to bed, and troubleshoot it in the morning. Otherwise, I do bad things. (One time, I accidentally infected my computer with a virus and tried troubleshooting it. It was midnight, and I did something wrong and it wouldn't boot and I ended up having to crash it.)
For a concrete example, with my display adaptor thing, I just switched it to the crappy default adaptor and in the morning figured out what to do.

What are yours?

 

[Perfection]

It's never the hardware.

 

[Genocidicbunny]

For gods sake, if it is hardware, discharge static electricity ( just touch something thats grounded and dont wear socks on carpet while working inside a pc).
When a pc BSOD's, write down the important info: name of BSOD, stop codes. Those help greatly when troubleshooting.
if you dont have the OS information handy ( serial key, etc). Make sure you write it down. So in case you do kill the OS, you can reinstall it.

 

[aimeeandbeatles]

Always have a boot disc handy. Even if it's a different OS, such as a Knoppix disc. So even if a computer's OS does die, you can take out the files.

If a computer is physically dead, don't throw the entire thing out -- rip out the good parts. Or sell it to someone who can. (My mom says she once got like 100 bucks for a dead computer that she paid 50-75 for. The guy used the working parts to build another.)

 

[GoodGame]

Stay calm. Rushing can cause more damage.
Always recheck the connections first.
There's probably one more permutation of configurations to try before you should give up.
Get all the details and Google it.