680 still worth it nowadays?

Solution
no the newer 900 line are faster and use less power. also with windows 10 ms is pushing newer direct x 12. also newer pascal gpu will be dropping. with then if the leaks are right there going to be 2x as fast as the 900 cards are now.
Benchmarks are easy to find. This one includes current offerings and a price vs performance ranking.
http://www.videocardbenchmark.net/gpu.php?gpu=GeForce+GTX+680

The GTX 960 has slightly more performance, but uses far less power and more modern, That can be had for > $200

I see the GTX 680 2GB version for as low as $150, and the 4GB version for at least $180.

Honestly, I would just get the GTX 960, it's a good card and much more modern, thus it will last longer as newer games come out.