I believe you can install the RPMs with software manager or urpmi, and they may not conflict with Xfree86 3

However you could install mandrake 8.2 which is good

Also with NVidia you should probably install their driver - it isn't GPL but works very well especially the opengl which is very nice indeed.

Their driver comes in two bits - kernel and user - you install the user as an RPM (can get a kernel RPM too but only if u use the normal kernel)

Then after installing the RPM of the driver and the kernel bit (via RPM or not), make the edits their readme says to /etc/X11/XF86Config-4 (which involves about 2 small changes), and X should work fine.

You definitely want XFree 4 though as you probably won't get any decent accelerated 3d in XFree 3