I haven’t written about my IIsi clock-chipping results yet because it did not turn out as planned. It took quite some time to perform the mod, and when it was done, the machine only gave me error tones when powered on. Today I had a few moments to better assess the situation. I confirmed what I had feared – that I had cut a trace on the motherboard while replacing the crystal. It was a trace going to the memory slots, which explained why I was experiencing ascending tones indicating a memory problem. I repaired the severed trace today and put the machine back together only to hear the same tones. After testing multiple configurations of memory, I determined that the machine will boot if all RAM slots are empty. Well, it doesn’t actually boot because it says that System 7.5 requires more memory to boot. Perhaps System 6 will boot? Anyway, I may have ended up sacrificing all memory expansion for a 5Mhz increase in clock speed. Pretty bad numbers, eh? Oh well, I’m sure to come across another IIsi logic board someday. :) In the meantime, if anyone has any suggestions for me, please let me know.