Sapphire or MSI?

The 650 Ti Boost which crushes the 7770 / 7790 and even beats the 7850

http://www.tomshardware.com/reviews/geforce-gtx-650-ti-boost-gk106-benchmark,3463-11.html

With the Radeon HD 7770 at $120, Radeon HD 7790 at $150, and Radeon HD 7850 above $180, Nvidia is rendering all three products ineffectual at their respective price points. With one swift stroke, the company engineered a hostile takeover of the $100-$200 market, increasing graphics performance at any given budget in that space.

As you can see here...the "performance per dollar" of the 7770 is only 86% of the 650 ti Boost .... however if the games offered to sweeten the deal on the 7770 are of more interest than the $75 game coupon on nVidia's bundle, that may sway ya thoughts in this regard

http://www.techpowerup.com/reviews/NVIDIA/GeForce_GTX_650_Ti_Boost/27.html