Don't worry. PCIe is backwards compatible which means that you can run a 3.0 card on a 1.0 slot. Besides you check what slot you have on the motherboard not on the CPU details and as you can see your motherboard supports 3.0
Would it be a waste to get a 690 over like a 670 or 680 then? The mobo is PCIe 3.0. If the CPU is running at 2.0 does that mean the the GPU will be slowed to PCIe 2.0?