Just throwing in a suggestion, you need a computer to do your homework on, but you also need to not have games installed on it to do your work due to temptation (Trust me I had this problem in highschool and college, to the point I had just below 50% attendance in both and ended up doing everything the night before).
Did you ever consider going to a local library to do your work in?
1) They're quiet, meaning you can concentrate on your work
2) It's a different environment; people tend to be more productive by having a "play" environment and a work environment. You play games on your home computer, you will be more tempted to go for the more fun option 9 times out of 10.
3) It's not your computer, it's the library's. Knowing you have a time limit on the computer. (The library has to shut at some point and they're not staying open late just for you) will push you to work ever more
Heck, I force myself to the University library because I know if I'm at home I'll browse the internet or plays games and I'm 20 years old.