Terrible performance/lag regardless of build/settings..?

[rokclimb15]

The older builds are less taxing (and less accurate). It's true that your rig isn't up to snuff for certain games like LoZ: SS. LoZ: WW should do just fine on that hardware though. I'd use that as a testcase. Then post your settings screens, temps, and a screenshot showing framerate.

edit: Xenoblade is probably a no-go on that hardware as well.