I have a 7200/75 with 112 MB RAM, a generic 19" multisync monitor that works fine with the internal video, MacOS 9. When I switch to my V3 card (latest V4/5 driver and beta 12 flashed ROM)it works great for 2 -3 hours. I then start having problems with vertical banding, partial screens and it finally locks up. Rebooting helps until it happens again. I do not have the 7200 Graphics Accelertion extension installed.
Any help would be much appreciated.