回複：小弟剛掙...

Since you don't know anything about hardware, I'd recommend that
you read some online articles first to get some basic knowledge.
Then you can read some reviews about motherboards, graphics cards,
cases, power supplies, etc. After that, choose components online
or at the local stores which fit your needs. Be patient.

Here are some articles.

http://www.buildeasypc.com/
http://www.hardwarecentral.com/hardwarecentral/tutorials/109/1
http://www.pcmech.com/byopc/

Good luck.