had a few hdd problems recently so used ccc to backup volumes, move them around and so on.
somehow i 'broke' the installation so that whilst it would still boot i needed to hit return during the boot and sometimes needed to press the power button when the boot got stuck.
all of that i probably would've lived with, but then i noticed that the micro server was only running with one cpu core.
after several hours of looking at the OP and trying different options a simple reinstall of chameleon 2.0 820 gave me an interaction free boot and both cores back.
so just came back to say thanks to Janitor (again)