what would you think about this: http://ca.pcpartpicker.com/user/masterboy9/saved/RV7G3C
That's a good build, but if you can take a very minor hit on CPU performance, I'd recommend the similar i5-4460 CPU instead which can be as much as $35 cheaper than the i5-4670.
You really shouldnt be going under 600 to 700 dollars for a computer, that wont play many games at 1080P and will have to go with low settings, but this http://ca.pcpartpicker.com/p/ct4n99 will probabvly run mid to high on demanding games, and high on casual games.