I managed to install this successfully on a Gigabyte GA-MA69G-S3H and an IDE disk.
Now, one of the problems remaining is my RAM being detected as 2GB 32MHz, which is a bit low for a 800MHz dual-channel setup.

What could be the reason for this?

I have a Gigabyte GA-MA69G-S2H and it reports the same memory speed. It's not actually running that slowly though. OSx86 runs REALLY well on that machine.

Download and run xbench. Compare your memory results against some of the results posted in the "xbench scores" thread and see for sure...

Ah true, RAM speed seems quite normal.
Thanks!

Now I need to find out how to boot the 9.2.0 kernel which should have been installed too, and somehow get rid off the need for cpus=1.
Does that work for you (as you have a similar board)? Do you use EFI+MBR?

Change your info if you have to with the Strings, about this mac

That's my "3rd working Zephyroth install" and It's still running 10.5.1... I haven't tried EFI or 10.5.2 on that machine. Never had to use "cpus=1" though. Mine uses the RTL81xx gigabit lan adapter which was supported natively by 10.5.1. Doesn't yours?

LAN works fine, even IPv6.

But both 10.5.1 and 10.5.2 only boot up with cpus=1.

For the 10.5.2 install I realized that something went wrong with EFI.. it didn't get installed at all.
Just saw that EFI wasn't installed at all, and 10.5.2 does not detect the SATA drive, while 10.5.1 does. Maybe you're good with keeping 10.5.1 :)