The perplexing thing about this card is if it actually runs the CPU at 50mhz (which would mean an external clock of 100mhz; I'm sure at least some of the people here are familiar with the 68040 "double-clock" lie that actually made it into some Apple sales literature) it's an out-of-the-box overclock; Motorola didn't sell the '040 in speed grades faster than 40mhz. (If the card *was* exploiting the lie in its name then that "50" would actually mean it's slower than the Q650's built-in CPU, so... yeah, that doesn't make any sense.)

I almost wonder if it could actually be a DSP card of some sort, not a 68040 under that heatsink. I think some of them came in ceramic packages about the same size as the '040, can you count pins (looking at the back of the board) and verify the pin grid array is actually the same?

Or maybe it's a super-secret never-released 68060 upgrade!