Just by pure curiosity, I checked what we have here. This seems to be a 2nd generation 68040 which is the result of a die-shrink to 0.65um compared to the first generation with a 0.80um mask. Which means that it still runs hot, but not quite as hot as the first generation 68040. I would still recommend a fan at 40Mhz. Unfortunately, it still includes the same errata as the first generation 68040 (it's only a die shrink, not a new mask). The 68040 errata are not quite as serious as the 68060 errata, and I'm not even clear whether any MC-qualified 68040s even made it to an Amiga. Most of the errata are pretty harmless and can be worked around or do not even apply when applied in an Amiga, though there is one particular bug in MOVE16 that may impact the reliability of this instruction in the presence of a Enforcer-like tool. Unfortunately, MOVE16 can invalidate the incorrect cache-line in the presence of an INVALID MMU page - which means in particular that some cached, but not yet written back data can be lost by pure chance. Not that MOVE16 has a couple of other problems on the Amiga anyhow and hence should be avoided...
