Video card for 1090t?

My wife's desktop has a 1090t @ stock speed 650w psu. It currently has an old 560ti in it. What would be the best card under 250.00 for single screen 1080p gaming that wont be too fast for that cpu? We game together and I feel bad when she has to turn down her settings and I don't.

Either a 7870 Tahiti LE, or a regular 7870.

the 7870 is right in that price bracket and the 1090T shouldnt bottleneck it much if any at all, depends how the games coded though.