I am looking to build a computer from about $1200. I have two different builds, one with AMD, and one with Intel. The AMD build is an FX 4100 (no O/C), an AMD Radeon 7870, 8 gigs of ddr3 1600, 500gig 7200 RPM hard drive, and a 750W psu, along with Windows 7. The Intel build is the exact same except it has an I5-3550 (no O/C), and a 650W psu. However the Intel build supports PCI e 3.0 while AMD supports PCI e 2.1. I do plan on utalizing Crossfire X. Which one is a better build for gaming (as both processors score pretty much equal on the futuremark website), and which one will be more "future Proof"?