One thing to note about the Sonnet G4 1 GHz upgrade is that it downclocks the bus to 66 MHz on a B&W or Yikes! machine. I suppose this makes manufacturing easier, and it is in tradition with Sonnet's zero-configuration upgrades. Nevertheless, I don't know the actual reason Sonnet designed the card this way. I think that the 700 MHz and 800 MHz G4 upgrades also clock down the system bus to 66 MHz. In fact, I think the fastest you can go with a G4 ZIF on a 100 MHz bus is 600 MHz with the XLR8/Daystar 7410 G4 ZIF upgrade. No one but Sonnet makes anything faster than that, and Sonnet's upgrades are locked to 66 MHz.
Peace,
Drew
