Get a laptop
Now allow me to rant.
I haven't been to your school but i can tell your right now that people at your dorm don't care if you get your studying done there. The night you need to get some actual work done on your desktop computer they will throw a party at the adjacent dorm. They will turn the music up so loud that you can't hear your own thoughts! They will yell and laugh so much that you think they are having seizures!
Second worst enemy to working in your dorm is your roommate. Even if you are friends before college life, when you study he will transform into a demon that is obsessed with bringing over friends when you are trying to get work done and making unnecessary noises to see how far he can go before you snap.
With a laptop you can escape from your dorm room and get work done at the library. And don't make the mistake of seeing allot of on campus computers that you think you can use. When you need to use the on campus computers everyone else will need to use it too! And there will be none for you.
Also if you are like me and bump rides to come home for break you can forget about bringing home a desktop, there ain't no room.
Even if you are doing graphics intensive stuff the current G4 memory bottle neck is so sever that you would be better off getting an 12" ibook and pumping it full of ram (third part of course).