1: Compatibility. This is a mistake that I've made many times. An ATX motherboard probally won't fit into a Micro ATX case. Also, some ATX or Micro ATX motherboards will not fit into the compatable form factor case. I know a person who bought a Micro ATX case and motherboard off of newegg, only to find out that the motherboard was half an inch too big for the case. Make sure to compare measurments of the case and the motherboard before buying.
2: Expandibility. If you are planning to make a top of the line dual processor server, don't put it in a case that only has two 3 1/4" drive bays. Also, if you are planning on building a small word processing computer, don't go out and waste money on a Lian-Li full server case. Get a case that has has the appropriate amount of room for expandibility.
3: Cooling. this will be your best friend, and your worst enemy when it comes to computing. Too little, and your processor is a $150 piece of burnt crap. Too much, and your computer will sound like a wind tunnel. The first thing to look at is, how much heat will your components give off. Here is a small equasion to figure out about how much CFM of air each your fans should move: (p²·f) where p= processor speed, and f=the number of fan openings. This equasion is not guaranteed to work in all cases.
4: Looks. Not exactly the most important part, but it is a thing to ponder. If you are making a awesome gaming rig, you would want to have a window, nice color, and mabye some lights, not a putty colored box. Try to find a case that fits your personality, and your wallet.
In part 2 of this tutorial, I will recommed cases for different applications, and prices. If you are looking for a case, post what you are looking for along with the specs of your other components, and I can try to help you find... The Perfect Case.


