I found a guy on ebay that has been flashing pc geforce3 cards with the mac rom and testing them in the g4 tower. He even bought a cube to test the cards to see if they will fit in the cube. I received one from him (he even provided installation instructions), installed it, and am seeing great performance. The best part is, its cheaper than what the OEM Apple geforce3 cards are running and fits easily (only 180mm long). If you are interested in contacting the seller, email me and I will forward your contact info on to him. Seth