Originally Posted by simpaty

Hi there,

I was able to succesfully install IPC 10.5.6 (upadted now to 10.5.8) on my P5k with a Q6600. I have installed it on a USB HDD, using a GUID partition.

However I have an issue that is sending me crazy. I have searched all over the internet to find a solution bu no one seems to have my same issue (not conforting at all!).

I have a dual boot system with MAC OS X (updated to 10.5.8) and Windows VISTA X64 (Chameleon 2 RC2 works like a charm!). All works great (Shutdown and Restart is not a problem!). However Whenever I switch between the two OS, I have to manually go into the Bios and play with the following BIOS flag:

ACPI APIC support.

If I want to log into MAC OS X, I need to disable this option, otherwise MAC OS X won't load and will reboot soon after I try to boot it.

Unfortunately Vista x64 has the same issue, only the other way around
It will not boot unless I Enable APCI APIC support. If i leave it disabled MAC OS X would work, but VISTA would not boot up!

Does anyone know (or guess) what can be wrong with my system?

Thanks to all for this magnificent forum!

Simpaty