If you truly want 8x AGP. Replace the clock generator in the motherboard. The AGP clock isn't based off the FSB. IT has its own external clockgen, seperate from the FSB gen. so you can give it a 133 unit (from the 66 unit) and set the AGP multiplier to 4 (4x AGP) (133x4=533) and you have 8x. The only problem is that the 66mhz AGP clock gen also powers the 66mhz PCI devices (just without multipliers), AKA your AMD southbridge will now be feed 133mhz PCI. But if you have a VIA southbridge (686B) you don't have to worry because the northbridge has a seperate clock input for 33mhz PCI devices, that has nothing to do with the AGP clock. Basically double the AGP gen you get 8x agp and all your 66mhz PCI devices are disabled. Everything else remain the same. Also remeber that 8x uses a lower voltage (.8) but I think that if the card is backwards compatible to 4x (1.5) it should be tricked into doing 8x AGP with 1.5 by giving it a 533 clock.