OpenGL & RedHat 7.1

[Mark Myers]

I have an ATI Xpert 128 AGP video card w/16MB RAM.
When I used Windows, OpenGL was fine.
Having switched to RedHat, anytime I try to run anything that uses 
OpenGL, the computer freezes and I have to log in via a ssh connection 
and reboot the computer.
I have tried this both in RedHat 7.1 & Mandrake 8.0 & 8.1.
Is there something special I need to do to get OpenGL working on my machine?
Even the GL screensavers lockup the current session.
My system is an AMD K6-2 450MHz, 256 MB RAM, 43 GB combined hard drive 
space, and the ATI card.
Any suggestions?
Thanks.
Mark

PS Where is the spell checker in Mozilla 0.9.5?