I take it you mean Xorg.0.log But no, no errors or even notable warnings there (just that there's no mouse specified etc). The last three lines logged are
(II) fglrx(0): Acceleration enabled
(II) fglrx(0): X context handle = 0x1
(II) fglrx(0): [DRI] installation complete
and then X hangs and I have to reboot.
Interestingly enough, when I tried to revert back to the radeon driver (after first building the ATI driver myself, then trying livna.org's version) it didn't work either - it, too, caused X to crash, with
(**) RADEON(0): MC_FB_LOCATION : 0xc7ffc000
(**) RADEON(0): MC_AGP_LOCATION : 0xffffffc0
(**) RADEON(0): Map Changed ! Applying ...
and then nothing.
I'm puzzled. I guess either my card is fried (which seems unlikely) or I'm getting an ATI bug here (and my radeon driver is gone?)
Does ATI's driver, if installed via RPMs built as instructed on Phoronix, overwrite the Xorg/Mesa libGL? Any idea?