Yep it will work on a 1.0 PCIE. They are backwards compatible. Also notice Linus uses q6600 in his scrapyard wars and pairs it with a 7950 which is more powerful than a 950.
As of bottlenecking, no bottleneck. Those are a decent pair and would play medium settings fine at good fps. Higher settings might suffer. Bottlenecking means when a component throttles due to another component Working faster than it can handle. That is bottlenecking. What you are trying to ask is if the parts limit each other's capabilities. A hardware limitation not a bottleneck.