I have a 5750 and a fresh install of lion, but when i enable my card in the ati5000 kext i get full res, but applications like ableton and traktor crash instantly. they all load perfect when i delete any ati kexts, but i end up with graphics adaptor only showing 3mb and low res.
my crash log when starting the apps look exactly like what this guy posted in the ableton forums.
http://forum.ableton.com/viewtopic.php?f=1&t=167470&view=previous
I've tried many methods of getting my card functioning properly but can't figure it out