Regarding freezing, i found the solution for me
Okay... here's the deal... I mentioned enabling the clock panel to set my speeds down.
My manufacturer clocked my G84 (-300? the GT part..) at higher speeds. 620/800.
Setting this down to 540/700 as speced by nvidia for the chip, the problems go away. (I have 16 screensavers in 2x2's across the 4 desktop cube faces, running smooth and reliable, and have been playing with the KVM features of F7 as it runs)
Now I just want to figure out how to tweak my card's bios to run at spec by default....
Boo to the manufacturer (XFX) for not at least burning in their pushed-spec cards in to catch when they've gone too far.