A few things to consider. First either with the newer kernels or all 64 bits (I'm not sure) the files are put at /lib/modules/.../drivers/gpu, so this might explain install error.
Second, the autoinstaller needs 32 bit libraries to install, even on a 64 bit system. I haven't got fglrx working yet on a 64 bit system.
Update; I did just compile a 126.96.36.199 kernel for slackware64-current.
The catalyst autoinstaller 9-6 worked fine, no patching required. This means 32 bit libs are not needed or slackware64-current now has them.
For the 188.8.131.52 kernel the autoinstaller puts fgrlx in /lib.../drivers/char/drm and not /lib.../drivers/gpu, although it probably doesn't matter.
My system is hd3200 (780g)
edit: removed comment about sound over hdmi not working. I forgot to unmute it. alsamixer -c1. Too many versions running.
You may wish to compare your kernel config files between the two machines.
But, if all other things are equal to your two systems, I would think the problem must be due to the graphics card and the driver parts unique to it.
For distribution, maybe consider: ubuntu, fedora, slackware. Seem to be more users of these.
What is sax2 anyway?
Bridgman: I never knowingly run aticonfig --initial. Maybe the catalyst autoinstaller runs it? After I install new catalyst, I review xorg.conf, see nothing new, and copy my old one back over. Why should this be run?
I don't know exactly what aticonfig --initial does but it seems to be the only "absolute must do" stop in our installation instructions, and whenver I talk to our devs one of the first questions they ask is "did they run aticonfig properly ?".
Post 10 goes to a level of detail I don't really know with fglrx; probably should get it into a bugzilla ticket so the devs can see it.