I'm runing hardy 64 bit on a thinkpad t61. Xorg = 7.3
Are you using fglrx to get opengl 2.0 support on r300? I was under the impression that the OSS driver doesn't have the bits for it included yet.
The only reason for using fglrx (on this laptop) was that I knew off-hand how to setup a vertical big desktop - I just didn't have the time at that point to learn how to configure the OSS driver. Btw, the intel chip was a breeze to configure - just typed the mode ("1440x900+1280x1024") and xorg picked it up at once. Great!
Anyway, for now I'm content using the x3100 for 2d work and mesa indirect for 3d development on the go. Back home, I test on a R500 and a G70 - with the target hardware being a quadro 3-thousand-something. A strange combination, but you get good compatibility (and become familiar with all shorts of driver quirks...)
Once the x3100 gets stable GL2 support now, I'll be happy.