I don't know if this will work for any other board I have an Abit AN8-ultra
This doesn't work with latest medevil driver but with the one from Zeph's 10.5.1
Installed inside IOATA kext "don't know if this makes a difference"

Don't turn off any ide or sata in bios
Do change from auto to none under each device in bios that does not have a device attached

Result = No waiting instantly boots into OS

I tried to put AppleNForceATA inside the Plugins directory of IOATAFamily but performances were less high than if I put it in Extensions directory.
So it must be different for each systems.

I can add your advice in the wiki if it works for other peoples.

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Mac OS X 10.6.3 • 2.8 GHz Intel Core I7 860 • ASUS P7P55D • 2 GB 2 Ghz DDR3 • ATI RADEON XFX 4890 1GB • 2 x Hitachi 160 GB Serial-ATA • PIONEER DVD-RW DVR-112 • LaCie Desktop Harddrive 750 GB USB

Not sure aobut overall disk performance, but the system feels more responsive.
But the main thing is boot time.
From pressing power switch to being in osx less than 50 seconds
from bootloader message to osx in about 18 seconds

hmmm... my results were nothing like this. it actually reduced my boot time by 1 - 5 seconds and still sits at a total of about a minute and a half and I lost DVD support via my SATA controller. I've switched back as my motherboard only has SATA (no IDE) and I still write with an external burner. ah well. we'll keep hoping for someday in the future.

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