No, no, no and again no.
The multiplier is always on the CPU card.
There were two versions of the 8600 and two versions of the 9600 and only the later versions lacked the logic board cache (because it was on the CPU card). So it is not correct to say that the 8600 and 9600 didn't have logic board L2 cache. The PM8600 Enhanced did not. The PM9600 Enhanced did not. The original PM8600 and PM9600 did.
The card probably doesn't specify the 8600 or 9600 because those machines didn't exist when the card was made.
The architecture of a PM8500 logic board is identical to the 7500 except for a couple extra chips on the 8500 to enable video out (or was that capture?). The only reason such a DP card would say not to use it in a 7500 is that someone thought the power supply might not be able to handle it.
Bus speed support was exactly the same in all 7500/8500/9500/7600/8600/9600/7300 machines. They all used exactly the same chipset. Perhaps there was some individual variation in logic boards such that some are better at higher speeds than others, but they should all manage 50 MHz. The ones (especially clones) that lack an L2 cache can often go as high as 60 MHz, however, the CPU card needs to be bus speed aware and set the Clock ID pins to tell the Hammerhead memory controller to change timing to support the higher speed.
I've seen 62 MHz in PowerTower Pros and Umax S900s with a PowerLogix PowerBoost Pro 604e/225 card which uses a little microcontroller to set the Clock ID pins as the bus speed is set higher.
Most of the time when someone can't get better than 45 MHz bus speed, it's because the CPU card(s) they're using don't set the Clock ID pins properly, not because the logic board won't go faster.
The multiplier is always on the CPU card.
There were two versions of the 8600 and two versions of the 9600 and only the later versions lacked the logic board cache (because it was on the CPU card). So it is not correct to say that the 8600 and 9600 didn't have logic board L2 cache. The PM8600 Enhanced did not. The PM9600 Enhanced did not. The original PM8600 and PM9600 did.
The card probably doesn't specify the 8600 or 9600 because those machines didn't exist when the card was made.
The architecture of a PM8500 logic board is identical to the 7500 except for a couple extra chips on the 8500 to enable video out (or was that capture?). The only reason such a DP card would say not to use it in a 7500 is that someone thought the power supply might not be able to handle it.
Bus speed support was exactly the same in all 7500/8500/9500/7600/8600/9600/7300 machines. They all used exactly the same chipset. Perhaps there was some individual variation in logic boards such that some are better at higher speeds than others, but they should all manage 50 MHz. The ones (especially clones) that lack an L2 cache can often go as high as 60 MHz, however, the CPU card needs to be bus speed aware and set the Clock ID pins to tell the Hammerhead memory controller to change timing to support the higher speed.
I've seen 62 MHz in PowerTower Pros and Umax S900s with a PowerLogix PowerBoost Pro 604e/225 card which uses a little microcontroller to set the Clock ID pins as the bus speed is set higher.
Most of the time when someone can't get better than 45 MHz bus speed, it's because the CPU card(s) they're using don't set the Clock ID pins properly, not because the logic board won't go faster.