Before I splurged on a Radeon 5xxx card, I wanted to make sure it would work in my motherboard. According to the specs, my P35-DS3L supports only PCI Express Version 1.0. The ATI 5xxx cards I've looked at are PCI Express 2.1. Are these cards backwards compatible with my mobo? I've stumbled across at least one report where XFX support recommended that a user downgrade to a 4xxx series card due to compatibility reasons. Has anyone here experienced any issues using a 5000 card in a Rev. 1 P35-DS3L, or any other PCIe 1.0 mobo?