My Apollo '040 25 has been successively overclocked for the past three years, first to 28Mhz, the 33Mhz and finally 40Mhz.
Obviously I've added a heatsink under the CPU fan, and having the whole ensemble mounted in a tower helps a lot. Even in the UK's current record breaking heat, I'm still running reliably.
Lando, you are technically correct as older '040 CPUs were not very tolerant of overclocking. However, more recent versions of the 25Mhz chip are reputed to be manufactured to the same tolerances as the 40Mhz version, the only difference allegedly being the part number. If the CPU is in a ceramic case (the processor part code will read MC68040RC) then it will be better able to shed heat. If in doubt, add a fan. The add a bigger one :-D
