honestly... please share what type of graphics would you think is acceptable for you when playing Diablo 3? there are various resolution and visual enhancement that you need to define...
Basically if you want a notebook that can play games, almost any brand and models can do that... the only difference is what type of performance you hope to achieve?
I do not think you can get a gaming category notebook with your budget... look more on multimedia type of notebook rather than hardware designed for gaming...