Thanks everyone!
Now I didn't compile it! (IMHO - there's some way to go yet until Linux will compete with Windows in user friendlyness when it comes to installing and configuring new programs...)
Now I found a new ati.2 driver - tried to install it - and now I'm reinstalling (from scratch, that is) Red Hat 8.0, as the result were that the X-server could't start after reboot.
I'll get back to you all when I'm up and running again...
I haven't given up yet - but it's rather anoying
Thanks again for you time.
Dr. Fresh