As I and others have said, Pascal is said to bring a very large performance boost over maxwell. So if you have the funds for a 980ti wait and get high end pascal, it should be much better. If you need a GPU over integrated go for a 100$ card as I said earlier. I would wait if I was you, I got the 980ti when the one I got came out and I will still get Pascal when it comes out. But choosing between them, go pascal.
An article: http://www.pcworld.com/article/2898175/nvidias-next-gen-pascal-gpu-will-offer-10x-the-performance-of-titan-x-8-way-sli.html