Matt_H wrote:
Yes, it's a top-of-the-line 68000 at 20Mhz. Maybe I didn't look hard enough, but the only crystal on the 600 motherboard I saw was clocked at 28Mhz. Same with the 1200. I assume there's a dividing value somewhere else. The 600's default 68000 is actually an 8Mhz chip clocked down to 7. Time to check inside the machine again...
Yup the whole system comes off the 28Mhz crystal.
Thus the A500's 68K runs off a 4 times divider... and the A1200 runs off a 2 times divider.
As for over clocking the chipset... I don;t think so. The parts were never designed (or planned) to run faster than 28Mhz, and I think there were other timers on the system which would get out of sync if the system clock was changed.
Still it would be fun to try. The Monitor output would probably be totally unreadable though, I don't think the components used were high enough quality to run at those speeds.
IIRC Motorola actually ran the 68000 at 50Mhz in their own labs, but I don't think a comercial version was ever made. :-)
