The dump seems to point to an ATI driver issue with handling the DMA request Windows made of it. Either the driver is at fault, or the hardware beneath it is (either way, there's no real way to say for sure). It looks like you have the August release of the ATI driver suite, which is probably the 10.8 catalyst suite. I'd try downloading and testing older versions in 10.x, as far back as you're comfortable, to see if any other versions make your system more stable. If not, you probably want to contact AMD/ATI to test that video card's hardware or the driver if you've already passed Prime95 and FurMark stress tests.