(NOTE: I'll be updating this post in order to keep a readable compendium - feel free to add comments if new "discoveries" arise)
1) Don't wrap it up, before having tested it
Whatever you do, verify it before screwing everything back together.
This includes: Closing the chassis, tying cables together for clean looks, unmounting screen/keyboard and putting it back into the rack, etc.
...and after all: boldly assuming one did not overlook anything or made any error, brings bad luck
2) Hardware that lies around is very likely to fail when you need it
(in german: "Hardware die liegt, stirbt")
3) If it takes you more than 15 minutes to find suitable information on the web, whatever you're trying is either dead-simple or incredibly difficult
If there's an error you cannot find any information about on the web, it's solution is:
incredibly obvious, so noone wrote about it -OR- incredibly difficult.
But definitely nothing in between
4) If it took you more than 15 minutes to do something, write it down!
It's highly likely, that:
a) you will be happy to have that documentation any time in the future.
b) you can save someone else the time to figure it out
5) Are you sure it's plugged in?
No matter how experienced you are, NEVER laugh about the basic questions when searching for an error. (e.g: "Is it plugged in?")
6) When working on house electrics: Shutdown all computers - even if you are sure they're on a different circuit
7) If you have spare parts: Use them!
If you're debugging any kind of problem, which could be hardware-related, try it with another piece of equipment. Never assume anything.
And consider: There is even the chance that 2 cables are broken - but the 3rd one might work!
Don't stick your finger into a fan to test if it worksFor several reasons:
a) You might still need that finger
b) It's often better to use a bendable material, such as a cable-tie or a strip of paper
However you do it, make sure to gradually slow down the fan - don't stop it immediately!
