If anyone has suggestions about how I might be able to get this card to run OS X on my J700, I'd much appreciate it.
Here is a real long shot that also requires minor soldering skills. Pins 15 through 17 on the CPU card are Clock ID pins. These pins are either connected to GND or not in different combinations to tell the J700 Memory Controller (Hammerhead) what bus speed to expect and to adjust the memory access timing accordingly.
I don't know what hte different combinations do (I have the settings for 44 MHz and 50 MHz noted down around here somewhere) but there are only eight possible combinations. Usually the pins are connected by either installing a 0 ohm resistor or not between the pin and GND.
So, with a bit of work with an ohmmeter, it should be a simple matter to discover which resistor pads are connected to pins 15 - 17 on one side and to GND on the other side. Then you can try the eight possible combination (seven really, since one combination is currently implemented and does not work) and see if any of them improve your memory timing.
XLR8 had an in-house application which could adjust memory timing in software (presumably by tweaking the internal registers in the Hammerhead chip) but they never released it and my contact took a job with Apple and I lost touch with him. Sigh.
Some of the adjustable cards, such as the PowerBoost Pro (604e card) actually have a bit of logic to adjust those pin settings to match the bus speed you chose for the card. This is probably why the PowerBoost Pro runs successfully at up to 62 MHz in every machine in which I've installed it.
Jeff Walther
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