keep in mind that price may or may not rise with difficulty increases, no one can predict either price of btc or difficulty at the end of this year, so you can't assume 1.8 daily or fixed 3.75 price

and unless you have some proper space to keep those pcs that would be a problem, noise for one, and count every 5870 as 0.3kWh heater... with 10 of them it is no different than having 3kWh heater running 24/7...

edit:


you can expect 45% increase in difficulty just today, who knows what will happen in 2 weeks not to mention 2 months or more

(a)  I don't see an acknowledgement that the generation difficulty will increase greatly during that time, and that your projection relies on speculating that the BTC price will go up proportionally.

(b) I don't see the price of electricity in there. Oh, you get free electricity in your college dorm. For 60 computers?

(c) If you live in a hot place, even one mining PC will make the room too hot in summer.