Multitasking is some thing I will have to work around if my lappy does not permit.
i5 will handle it with swift, don't worry.
How much help does a dedicated graphics card gives? I mean what about RAM and processor and graphics card? At what point do you need a graphic card?
Dedicated graphics card gives help when you need visual performance (eg games, a bit of image/visual edting). Still, editing is mostly CPU based task, normally multi threaded. The probook is good but it lacks a dGPU and you can't get a laptop with i5+ good dGPU in your budget. Increase a bit and go for i5 + 7670M combo, you won't regret.