Hi guys. In a recent conquest, I got a Mac II (regular II, no letter afterwords), and a Turbo '040 card. No adapter, so I can't test it. The chip is marked XC68040RC33M, and from what I have read, it's a full 040, running at 33mhz. However, it has a oscillator (silver rectangular object next to CPU), marked 20.000000mhz.
According to this, if it were running at 33mhz, it would have a 16.5mhz oscillator. They say a 20mhz one makes it run at 40mhz.
Just want to get my facts straight about it.
There's a good chance it's a 33MHz part overclocked to 40MHz.
I think they just overclocked 33's to 40 since the 40's were rare (only the 840av used them and Apple probably had 1st pick).