Newbie-xwindows graphics server?

[user138]

I have a ATI 3D RAGE LT PRO that is driving a flat panel monitor,  I cant seem to find any video settings that work with this hardware?  has anyone used something similar?  the refresh rate is static at 60hz and uses resolutions 1024x768 800x600 640x480.  also is it advisable to use 32bit color, or should I just stick with 256 colors? any ideas would be helpful.....oh, I installed using the simple install could that be a problem? thanks, james