if the system is 10.5.4 right after install AND it support Phenom then I'm guessing it is LawlessPPC's distro. I had to look up your motherboard (over at Newegg.com) to make sure I knew what I was talking about and it looks like your board should see all the cores.

Couple Questions: when you go to /Applications/Utilities/Activity Monitor, do you see four boxes showing you your core activities? if so then your system recognizes it... but system profiler doesn't. Have you tried booting with the boot flag "cpus=4"?

There are numerous posts around this forum on getting your cores recognized with a SB600 southbridge chipset so you are no exception to this working. Hope to hear back with good results.

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