XFX RX 480 GTR
If you need a GPU but don’t have the budget for something like EVGA’s incarnation of the GTX 1070, then AMD has a good solution for you. For slightly more than half the price you can have a mid-range solution from AMD with 8GB of GDDR5 and Polaris 4.0. Drivers have increasingly given this little chip some more performance, and it can destroy 1440P with the highest settings for most games. 4K if you turn stuff down. It also runs cool, and relatively quiet for a Polaris 10 sample. We even use one as part of our performance analysis tests.
Being that time of year, you can find the XFX RX 480 GTR for around $269 or less. It’s a great deal and can potentially be a good upgrade.