Hey, don't put it off as being..
really difficult.. at first, I was like you saying, "Nah, I don't need that!" - i can just get an external optical drive, and boot usb the windows installer". - But, I decided one day to take the plunge into how it is done.. although I am proficient in Linux/freebsd, I am not that good at modifying grub bootloaders, but the windows hack sure was easy..
All you have to do is once your windows 7/vista is installed, goto regedit. search for iastor5 and msahci - go to these and change the start values to 0's - this will tell windows to search for ahci upon next boot up. Once you are done with the changing of those entries to 0's.. Your next and final task is to boot back into osx.
Here is the scary part.. you need to be careful that you don't mod the MBR to the wrong drive.. doing so can render your boot drive and or other drives unbootable or unstable.. The best way to do it I thought was to physically remove all drives except for the mac os x startup disk and bootcamp disk(if its on single drive all by itself).
Then run disk utility and left click or right click on the hard drive, not the slice! - and it will say what disk is identified with bootcamp.. say disk1.. the slice would be disk1s0 or something like that..
Once you have that.. run ahci.sh ./ahci.sh under root and it will automatically determine what drive is the windows drive - this should match to your prior to doing information on the bootcamp drive.. Then type Y for yes. It will then ask if you want to mod the mbr? type once more.. Yes and it will be done. You just loaded hex addresses of which will change the mbr to accept ahci.
Lastly, boot back into windows - assuming all went well, you should get to the desktop and windows will immediately start installing its own ahci 1.0 driver which is nice, but intel's is much better.. You then need the intel storage matrix drivers and once those are installed, you should get the following:
SATA AHCI controller ICHR??? something. Congrats! You now have ahci enabled on your 2009 mac pro, for 2008 - ESB is what is used. The only thing you still can't do is boot into windows under 2006-2008 mac pros, even though the ahci driver installed - again, this is a firmware issue and Apple can only provide the revision code so it will work - but knowing Apple, they won't do it.
My bad, not a driver issue. I read the AHCI thread a few years ago and concluded it wasn't worth my time to even attempt to get it working in windows.
Thanks for clearing up the details.
