are these specs alright to play a modern 2012-13 games?
i only wanna play minecraft
Wait, uhm, what? It'll be okay for minecraft, I suppose...
That being said:
1) The only reason your laptop can play bf3 on low settings is because of a very low screen resolution.
2) Especially with that new budget, please please PLEASE buy the parts and assemble them yourself. It's just like LEGOs for adults, and you'll get WAY better performance.