I have noticed Mirror as "not enabled" when using natit and Mirror as "not supported" when using EFI or the other way in system profiler. can you try them?

Quick question..do you use EFI for 8600GT in 10.5.6.. Does wake and sleep works propely in 10.5.6?..I have the same card...but having issues some issues as posted in this thread
http://www.infinitemac.com/f7/xfx-ni...e-ci-as-t2340/

Can you share with me graphics Kexts which you are using.

Thanks,
Nagu