Try to wait for one of the $250 1060 models. they almost all use 6 pin connectors and have very good performance for their price. the 1060 even out performs the 980 in some scenarios, not many though. But considering the price gap, its quite a deal. I advise to improve your PSU (power supply), this will give you more breathing space and therefore wont force you to buy a new one soon. If you are considering to buy a new PSU as well, make sure that it is silent, good rpm, and is at least semi modular. This allows better cable management, thus creating better airflow in our case. Hope this helped!!
This is a link to the gtx 1060 models:
http://wccftech.com/nvidia-geforce-gtx-1060-custom-model-round-up/