Looking at the priya site, they lead you to think that they go above 600 mhz if it has the 1.8 bios. Looking up a biw2b motherboard from procom, they say that their board stops at 600 mhz. So is there a definitive answer...not really. I'd say that you could probably put a faster chip in what you have. But if you put one in and doesn't boot, your usually not going to harm anything. There was a slight change in voltage in some of the later p3 chips that may not be recognized by your motherboard. They had 1.65 and 1.7 volts for earlier coppermines and 1.75 for later. Some bios's come up with a micro code error for the latest chips, since they weren't updated with the latest cpu info. That error doesn't appear to bother anything, as most test programs still see the speed that it is running at correctly.