kjaer wrote:
I have no idea what happens when you put a 735 CPU board with the older I/O, but since from a chassis point of view they're fully interchangeable, I have to ask.
Been there, tried that, the I/O board needs to match the CPU board or the machine won't POST.
Actually it's not *that* surprising, since part of the machine identification information used (and displayed) by the PDC resides on the I/O board (as well as the PDC itself) - in other words, it's the 735 I/O board which makes it a 735, as opposed to a 720...
Another fun thing to do on a rainy day, is to mix 735 (or 720) boards from systems of different speeds: mixing e.g. a 66MHz 720 CPU board with a 50MHz 720 I/O board will create a system where the OS believes (as told by the I/O board) that it runs at 50MHz, while the CPU runs at 66MHz because the clocks are separate. And then ntpd goes nuts trying to adjust your clock

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