The LC 475 is back for another round of experimentation! Remember that supposedly full 68040 processor I bought to replace the original 68LC040? The whole point was to gain the floating-point unit missing from the original processor, but things haven’t been going quite according to plan.

This time I’m using TattleTech to investigate exactly what the Macintosh thinks is installed. I’ve already had the machine running at 33 MHz, and now I’m having another look at what the replacement processor can actually do. Unfortunately, the results still aren’t quite what I’d expected from a full 68040. Where’s my FPU?!

Whether I’ve ended up with a mislabelled processor, a defective chip or something else entirely is another question. I can’t really declare it counterfeit just because the results aren’t what I wanted, but it’s certainly suspicious. At least the LC 475 itself has been taking all these experiments rather well. If only the processor would cooperate!