Home▸ Forums▸ MacNN▸ How can I upgrade to 500Mhz on a G4 400?? Thread How can I upgrade to 500Mhz on a G4 400?? MacNN Peripherals 9 posts View original thread ↗ Posts for this thread haven't finished importing yet. The full-archive import runs in the background; it'll pick this thread up in the next pass. In the meantime, the original source thread is still available.