Is there any difference between use driver from ati.amd.com or download fglrx package from repositories?

Question

I'm wondering if both are the same or one is better than the other.

Answer 1

A closed source driver distributed by another channel won't be much different as one can't recompile it. However some kernel configuration and heuristic around the kernel module might be more targeted towards your distribution (dkms, compatibility settings, device id's, etc.).

I strongly advice to use packages. It's much easier to uninstall it and it provides some level of knowledge on what changes are made on your machine. Simply running a script as root to install driver X, Y or Z makes me shiver as I give it all freedom to screw up my system. (analogous to install from regular upstream source software "make install" vs. installing from package management)

The downside of packages is that it usually a little bit older than the ones provided upstream. However, new versions might come with new bugs too.