It's kinda confusing, are you buying used computers? Why such old hardware? Phenom x4 9650 are OLD, and what i mean OLD I mean 4 generations back, about 5 years ago processor, that wont keep up for todays needs in gaming.
The I5 760 is indeed a better processor, still, too old if you are buying a "new computer" in your computer shop.
HD 6950 is better than the GTX 560ti. You are saying ---> "GPU Crossfired 6950's with unlocked shaders and 8GB Ram "
Which means 2 GPU HD6950 working together. Which means that its a LOT faster than a single GTX 560ti.
Not to metion that Unlocked shadders also says that it will improve better than a normal HD6950.
So, would please clarify? You are comparing a multi-GPU system with a fist generation I5 versus a Single GPU system with a firts generation of Phenom x4.
Also, if you can.... Tell us what or whom is offering those systems, and how much?