These three Options are said to be helpful when trying to play 3d games with an ATI graphics card and the proprietary drivers :
Option "Capabilities" "0x00000800"
Option "UseFastTLS" "off"
Option "KernelModuleParm" "locked-userpages=0"

My question is, what do these do, and what are the other options I could use? Is there a web page with all the explanations of all the options, so maybe I could tweak my setup myself (I have a radeon X1300 with driver Ver. 8.49.7)?

I have beryl installed and working, but everything is sloooooowwwwww. Glaciers move past me with every click. If I knew the right options, I could configure it better (I hope).

You will need to look in the ati documentation for your driver. These options are specific to the driver and not listed in the xorg.conf manpage.

Well, as I understand it, you need to set up XGL if you want to combine ATI and Compiz. Check google for details.

Thanks all; ati proprietary drivers are a pain in the A$$. I found many options online with google, and got things to "Work" - but the 2d performance sucked. so even though i got eye candy in 3d, i got glacieral response on most common tasks.
Whats worse is i got my wife using windows in a VM - so she blames linux for any/all problems! (she has no idea what we have here )
anyway, i went back to using the vesa drivers. they work good for 2d. In the future I'll get an NVidia card !