Will getting a better Graphics Card Help with Frame rate issues? I currently have an AMD Radeon R9 200 series.  I'm willing to spend ~$400 on an upgrade. I've heard Blender cannot really use AMD cards (or really any other cards that aren't Nvidia) very well. Will upgrading to an Nvidia card help with the 3D view frame rate? Its getting difficult to time more complicated movement with only a 10 fps preview (and yes, everything is simplified, no physics, Solid view, yadda yadda). 

I know using quick render is an option, but that's a lot of wasted time in the long run. 

Also, 

if I have an Nvidia card, could i change this from CPU to GPU? Would that also help better my Frames per Second? 

Thank you all very much!

Thank you all for your answers! The actual rendering isn't much of a problem since I often send the final renders to RenderStreet(A render farm). Viewport is the main thing I'm concerned about, and thanks to you all, I see I mainly need a better CPU ALONG with GPU, BUT that I also kinda have to wait for the big 2.8 update for the viewport overhaul.  

I wish I could checkmark all your answers, cause they all helped!
Yes, with Nvidia you can render using GPU and also you can use it for OpenSubdiv compute.

Is not true that computed device is only for rendering. GPU is used also for drawing viewport using OpenCL.
Only if you have 2 and more graphics cadrs, one is marked as "(Display)" this card is used for drawing viewport, other ones are only for rendering (and preview render in viewport)

BTW: for 400USD I highly recommend Nvidia 1070. The best ratio speed/price/power comsumption and 8GB VRAM allow you to render complicated scenes without "CUDA: out of memory error". 

EDIT: one important thing here: if you have very slow CPU, fast GPU don't raise fps too much, because they must work synchronized. CPU is "the boss" and send calls to GPU. Other words: CPU must tell to GPU what is going on and GPU work with this data.