sell off the 7850 and get the 290X if you can.
for good gaming at least for 3 years i suggest 290 if you have the budget
nothing is enough in gaming. in a few months even the 290X will have a hard time getting all games to run on ultra.
you are gaming on 1080p?
There's no guarantee, I've learned it the hard way, in 3 yrs DX13 will come and make most cards obsolete, so get a 280x, change every 2 yrs.
For 1080p, get a 280x or gtx 760 and save your money. In 2-3 years time, the then "mid-range" cards will be equivalent to a 290.
280x will max out for 2 years at 1080p?