I just recently flashed a Visiontech GF3 card to work in my sawtooth G4 unfortunately the screen flashes constantly with it. I have tested this card in a gigabit G4 and it works fine without screen flickering so it should work in any G4 computer exept the original and Yikes! based systems. I hate to give up this card because 3D Games rule and Quartz Extreme is truly awesome. I'll even throw in some software "Extras".
E-mail me at mrcorwin AT citlink DOT net to work out a fair price and shipping details.