[HOWTO] Boot Macs with Intel Chipset in AHCI Win7 Vista XP Linux

[chipster21]

Hi there,

first of all, sorry for my English, I'm Italian, so please be patient.

I'm trying to follow "ludacrisvp" tip by creating the grub partition but, I'm having trouble on third step "find /boot/grub/stage1", grub is returning this error "Error 15 no file found". Could you please help?.

 

My config is :

Mac Pro Early 2008 2 Xeon 2.8 Ghz & 10GB Ram, nvidia 8800GT

Bay 1 - 1TB for Time Machine

Bay 2 & 3 Raid 0 for my primary OSX & Data

Bay 4 (3 partitions) OSX (for testing), Vista Ultimate 64 bit and Windows

Data

 

P.S. I'm new to the Linux staff

BTW, I'm using Ubuntu 8.10 64Bit

 

Thanks in advance

 

Ciao

[chipster21]

Hi there,

first of all, sorry for my English, I'm Italian, so please be patient.

I'm trying to follow "ludacrisvp" tip by creating the grub partition but, I'm having trouble on third step "find /boot/grub/stage1", grub is returning this error "Error 15 no file found". Could you please help?.

 

My config is :

Mac Pro Early 2008 2 Xeon 2.8 Ghz & 10GB Ram, nvidia 8800GT

Bay 1 - 1TB for Time Machine

Bay 2 & 3 Raid 0 for my primary OSX & Data

Bay 4 (3 partitions) OSX (for testing), Vista Ultimate 64 bit and Windows

Data

 

P.S. I'm new to the Linux staff

BTW, I'm using Ubuntu 8.10 64Bit

 

Thanks in advance

 

Ciao

 

I fixed it.... Thanks anyway

 

Ciao

[gibbsj]

I'm having trouble on third step "find /boot/grub/stage1", grub is returning this error "Error 15 no file found". Could you please help?.

 

 

I cant get it to work. I have a 35 mb partition with the folder /boot/grub -- all the files are in there.. like the stage1

[chipster21]

I'm having trouble on third step "find /boot/grub/stage1", grub is returning this error "Error 15 no file found". Could you please help?.

I cant get it to work. I have a 35 mb partition with the folder /boot/grub -- all the files are in there.. like the stage1

 

Just be sure that the grub partition is the first one

 

Ciao

[sebhag]

Big thanks to ludacrisvp!

 

Did this a couple of month ago, but didn't have time to post till now...

 

Everything's working great now, but i did have some major problems along the way. All in all it took me three days and i completely screwed up my xp partition even though i had an Acronis image and successfully restored in the past.

 

I can't remember all the details, but first thing that went wrong was the repartitioning process with gparted. I thought i save some time by just adding a little partition at the end so it wouldn't have to move all the data. But for some reason gparted still took over an hour and screwed up my xp install. After several hours trying to restore XP i gave up, removed the bootcamp partition and started all over. Since bootcamp creates a dummy 200meg partition between OSX and Windows anyway i just ended up using that and formatted as ext2 so it wouldn't show up later. Forced drivers in XP, installed rEFIt and grub, booted Windows in AHCI and installed drivers properly.

 

Along the way, i also attempted installing grub on a memory stick with the purpose of just booting from the memory stick if i want AHCI which would then point to the partition on the SATA drive, but for some reason it didn't work - can't remember.

 

In the end i also removed rEFIt as i didn't really see why i would need it, but that might just be with my configuration. Set grub timeout to zero, xp partition as active and windows as startup disk. This was done on a quad-core Mac Pro (pre 2008). Windows with AHCI boots now by default and you only see grub flashing up briefly. If i want OSX i just use bootcamp loader.

 

The LG super multi is happy and I haven't had a single problem with BD-R or BD-RE. Enable BD-RE FastWrite in ImgBurn to get twice the speed.

 

Once again thanks - InsanelyMac is the daddy!

[ludacrisvp]

Thanks, it is nice to see that I have made some peoples lives easier by allowing them to use the hardware they paid for to its real capability.

 

rEFIt may not be 100% needed but it does make it easier in the beginning so you don't always have to hold the option key when you are booting back and forth between devices. Also it makes it easier for those who have many partitions to choose the right one to boot from. Before I had rEFIt all non Mac disks just showed as windows disks, regardless of it being linux or windows.

 

I decided not to use the 200mb partition that apple makes to keep the drive formatted to proper guid partitioning because you never know when apple might decide that they want to use that for what it was made for.

 

@sebhag - I am thinking of getting a Blu-Ray drive soon, what specific model LG do you have and would you recommend it or a different drive?

I too wasn't able to boot from a USB flash drive now that I think more about it, nor was I able to use the Super Grub Disc, this is why I chose the Live CD for Ubuntu.

 

@gibbsj - Have you tried starting from the beginning again, it is very easy to miss a step and then it just doesn't work.

[sebhag]

Here's the drive spec:

 

 

I love it, although there's a slightly faster Sony or Panasonic, but they cost considerably more. I picked up my LG for £150 and BD-R's take under half an hour, single layer that is.

 

Re 200meg partition, apparently it's there for no particular reason. Well ok, not quite correct - as far as i understand the EFI system partition is supposed to be used for bootloaders and other EFI tools but OSX doesn't make any use of it. Vista might - not sure, but will find out soon. If Apple would only update to UEFI 2.1...

[TallCoolOne]

Thanks for all this info, I finally got AHCI working in my Vista partition after many tries. I was trying with a GPT partition scheme drive and was not able to get it working, anytime i added the grub partition my windows would not boot anymore. Finally I tried with MBR and everything worked!...well almost everything...

 

Now I have a different problem, my new blu-ray drive (LG BH08LS20) shows up now in Device Manager after getting AHCI working, but has a little exclamation next to it, and in the device status says "This device cannot start. (Code 10)". I searched around and found others with this error having various solutions like removing iTunes, deleting some LowerFilters and UpperFilters from a key in the registry, removing the device from device manager and resetting, etc...but nothing seems to fix it for me. I'm at a loss for what to do now, anyone have any ideas? I do have another DVD-R type device in the machine and that one works fine. I am running Vista Ultimate, and installed SP1 also hoping it would fix it, but nope..

 

thanks in advance..

[ludacrisvp]

I don't actually have a Blu-Ray drive in my Mac Pro (I ended up upgrading my laptop to have a blu-ray because I wanted portable blu-ray) but here are some suggestions, try the other ODD_SATA port or try your drive in another machine or another SATA Cable.

Make sure you have the latest Intel AHCI drivers installed (you should see a piece of software called "Intel Matrix Storage Manager" installed with those drivers) because the included with Vista ones really are horrible.

[macpionier]

Hello ludacrisvp,

 

I have a question that is the direct opposite of the topic.

 

I take it that OSX natively use AHCI because the system profiler->S-ATA tells me something about ahci?

 

Is there any possibility to deactivate AHCI? I want to install an Solid State Disk and I`ve read a lot that disabling AHCI leads to a better performace using an SSD.

 

I know this is Windows world but I think it should be the same issue on a Mac. At least I want to give it a try and compare it with AHCI enabled.

How can I do this?

 

Perhaps you have a good idea?

[ludacrisvp]

Yes, OS X uses AHCI natively.

My best guess would be to use a non-modified grub bootloader (or another legacy loader like Lilo) and boot your machine into that loader then load OS X from that loader, in theory that would keep the system in compatibility mode while booting OS X.

Those in the OSx86 world may be of some help for you because you would most likely need modified kext files that would give you support for non AHCI version of your chipset. What Mac are you using a SSD in?

[TallCoolOne]

Make sure you have the latest Intel AHCI drivers installed (you should see a piece of software called "Intel Matrix Storage Manager" installed with those drivers) because the included with Vista ones really are horrible.

 

Thanks ludacrisvp!!! This did it. I had installed the drivers from the InfInst.zip from your third post, but not the Intel AHCI ones because your directions said to skip that step if using Vista. Maybe update the steps for Vista to mention to make sure to install those drivers also on Vista after getting into AHCI mode. Thanks again for all your help!

[TallCoolOne]

Ok so after I got all excited that it now works and I can watch blurays on my mac, I booted back into OS X and tried to start my Windows partition via VMware only to find this no longer works now. It boots into the grub bootloader but just says "GRUB " in the top left and freezes. Anyone know if it's possible to be able to use a Windows partition setup with grub for AHCI in VMware also? I don't need VMware to load the gurb bootloader in this case since it already uses AHCI, but it insists on booting into the grub partition.

 

thanks.

[sebhag]

Ok so after I got all excited that it now works and I can watch blurays on my mac, I booted back into OS X and tried to start my Windows partition via VMware only to find this no longer works now. It boots into the grub bootloader but just says "GRUB " in the top left and freezes. Anyone know if it's possible to be able to use a Windows partition setup with grub for AHCI in VMware also? I don't need VMware to load the gurb bootloader in this case since it already uses AHCI, but it insists on booting into the grub partition.

 

thanks.

 

Should be easy, I'm using a seperate partition for the grub bootloader so you can always skip it by booting from the partition with Vista installed using rEFIt. Same under VMWare, if you got grub on a seperate partition there shouldn't be an issue.

[thalar]

I am apparently missing something because I absolutely can not get grub to load. I have been working on this for the past 4 days following ludacrisvp's instructions as well as some suggestions by others with no success. My setup is as follows:

Early 2008 Mac Pro with two internal hard drives. The drive in bay 1 is Mac OS X only with Mac OS X 10.5.6 and all the most recent updates. The drive in bay 2 is Vista 64-bit only.

 

The Vista drive has 2 partitions: the 200 MB partition that Bootcamp creates (/dev/sdb1) and the Vista NTFS partition (/dev/sdb2). I have managed to get the boot directory created on /dev/sdb1 with the grub directory inside that and the modified grub files inside that directory. My first command at the grub prompt is 'device (hd0) /dev/sdb' which just echoes the command. However, when I issue the command 'find /boot/grub/stage1' I receive 'Error 15: File not found'. If I proceed with the root command 'root (hd0,0)' the command is echoed. I then enter 'setup (hd0)' and receive "Error 17: Cannot mount selected partition'. I receive this error even if I have manually mounted the /dev/sdb1 partition using Terminal.

 

Can anyone, please, tell me what I am doing wrong? I am using the 64-bit version of 8.04.2 of Ubuntu. The /dev/sdb1 partition is FAT32 but it does not mount automatically when I boot using the Ubuntu CD. I have to mount it in Terminal and I had to copy the boot directory to it using the 'sudo cp' command in Terminal as well. I don't know if this behavior is normal or not.

 

I would greatly appreciate any help.

 

Thanks!

[johnsock]

I have managed to get AHCI enabled (for real, not in legacy mode) in Vista 64 without using GRUB, rEFIt, or any extra partitions. I did this by modifying the MBR to perform the same configuration that is done with the modified GRUB stage1 loader. The end result is the ability to boot into Vista without going through any extra boot loaders and having AHCI enabled after installing the Intel Matrix storage drivers (without forcing the install). Also, I have access to all 6 SATA ports with NCQ capability. This was my primary motivation so that my SATA optical drive could be connected to one of the SATA_ODD ports on the Mac Pro motherboard and so that my Intel X25-E could operate full speed with NCQ.

 

I have not tried this on anything other than my Mac Pro (2006 model) running Vista 64 Enterprise. If anyone else is interested in this I'd be willing to work on trying it on other configurations and coming up with a guide (or possibly a utility program) for making it easy.

 

I want to thank ludacrisvp for this awesome guide that was my starting point on the project, pipomolo42 for the assembly code for writing to the configuration registers in the controller, and thestarman3 (http://www.geocities.com/thestarman3/asm/mbr/Win2kmbr.htm) for a great disassembly of an MBR. I just put the pieces together and figured out how to fit some additional code in the limited space available in the MBR.

 

If anyone is interested in helping, I'd like to check the MBRs from other versions of Windows and see if the code works on other Mac models. I will post some screenshots so someone can see that I'm not blowing smoke (or tell me if I'm wrong) and more details on the process if anyone is interested. If there is enough interest, let me know and I'll start a new thread. If I'm barking up the wrong tree or posting in the wrong place, tell me to {censored} off and I will, with no hard feelings.

[ludacrisvp]

@johnsock - This is a perfect place to post what you have so far. I have the 2008 Mac Pro so I could test your configuration as well to see if it works right on the newer machines. It would be nice to figure out a way to modify the Vista installation disc so that it has the modified loader to load the install from SATA optical drives.

 

As far as proof goes simply post an image similar to the one that I have below I have all 6 SATA ports in use and one of the IDE in use.

 

The modifications that you have made to the MBR would be interesting to look at. I briefly messed around with direct modifications to the MBR via a hex editor but they were not successful.

Let me know if you need any more information from my system since I have multiple OS running.

Vista 64 SP1

Windows 7 Beta 64

Windows XP Pro 32 SP3

Leo

Snow Leo

Each have their own dedicated drive.

XP is installed on an IDE drive, all others are on SATA.

 

We might be able to easily make a utility from one of the Vista activation hack utilities.

I will have to look into it more on my end.

[mchaggis]

Firstly, thanks a million to ludacrisvp for the OP, it's a beacon of light I haven't tried it yet though for 2 reasons: firstly it would be for my work computer and I can't afford the time either to do the procedure or for it not to work right now. Secondly, I have one of the new 09 Mac Pros so I wasn't sure if the GRUB module would work with the new chipset/southbridge. Any ideas?

 

And to johnsock - your method certainly sounds a lot simpler. If you have the time I'm sure I wouldn't be the only one offering to have your proverbial babies if you could come up with something relatively usable

 

If either of you (or anyone else) has something working and want to test it on an 09 Mac Pro, feel free to get in touch and I can test it for you.

 

As an aside: I installed Vista x64 without using Bootcamp (partitioned as GPT) and it booted fine, but still no AHCI. Can someone explain at what point the SATA controller is put into legacy mode in this config? It would seem to me (as a techy but without much knowledge of EFI and bootloaders) that Mac EFI must default to legacy mode but MacOS X must enable it during boot. Isn't this weird? Would there be any way of getting rEFIt to enable AHCI mode prior to a boot loader running? Like I say, I don't know a huge amount about this but if it helps, great...

[johnsock]

I'm glad to see some interest in this. I'd definitely like to come up with a simple solution that could be carried out by the average user. The idea crossed my mind about modifying the Windows install disc as well and I think it should be possible. I think that should be an ultimate goal once we have verified that it works on multiple configurations.

 

Here is a screen capture showing the controller and drives in AHCI mode, both in device manager and in the Intel Matrix manager. I also included CPU-Z and Windows Information so you can see it is a 2006 model Mac Pro running Vista Enterprise x64. I have three hard drives connected to the standard SATA ports and a DVD burner connected to one of the ODD_SATA ports on the motherboard. I don't have any PATA devices, but the ports still show up in device manager.

 

 

The drives on ports 0 & 1 are a RAID0 array containing OSX Leopard. The drive on port 3 contains Vista. The Vista drive was prepared using the Bootcamp configuration utility in Leopard so it only contains the 200MB EFI partition and the NTFS partition for windows. It is formatted GPT and is technically a hybrid GPT/MBR disk as is normal when using Bootcamp.

 

Here is a summary of what I did to get this working:

 

1. Use Bootcamp Assistant to create Windows partition on separate drive.

2. Install Vista using normal Bootcamp method, formatting the partition as NTFS during setup.

3. Install Bootcamp drivers from Leopard DVD and then update/install any other drivers needed.

4. Install 'Standard AHCI 1.0 Controller' drivers from Vista. This requires forcing a driver update manually and will result in a warning that the hardware doesn't appear to be supported.

5. Reboot Vista and allow device detection to happen, resulting in another reboot. This will get the generic Microsoft AHCI driver installed which gives access to the ODD_SATA ports, but all SATA ports still operate in legacy mode.

6. Once everything was verified working, I copied the MBR from the Vista disk and modified it with the code that modifies the port mapping register on the ICH for AHCI non-combined mode.

7. Overwrite MBR on Vista disk with my modified one and reboot

8. Allow another round of device detection to run its course and reboot. This will not actually change much, it just causes Vista to see the new PCI identifier for the AHCI mode controller and reinstalls the Microsoft AHCI driver and re-detects all SATA devices. At this point the Microsoft AHCI driver is running normally (not forced) but all devices are still seen by the OS as legacy mode devices.

9. In order to force windows to redetect the SATA devices I installed the Intel Matrix Storage drivers. This was done from the installer program, not using the .inf method. This works because the ICH is now recognized with the correct PCI identifier.

10.After another reboot and another round of device detection, all devices are seen in AHCI mode and all features are enabled.

 

The only thing I'm doing differently than the rEFIt/GRUB method is placing the configuration code in the MBR instead of in the GRUB stage1 loader. Here is an explanation of how I modified the MBR to make this happen:

 

1. Copy MBR from Windows disk:

- sudo dd if=/dev/disk3 of=./original.mbr bs=1 count=446

- make sure that you substitute the proper disk number where I have disk3 above!

- this will make a 446 byte file containing the boot code. Don't get the entire 512 byte sector because the other bytes contain your partition table. If you jack up the partition table you won't be able to boot Windows.

2. I used the DOS DEBUG program to unassemble the boot code so that I could modify it. I'm not going to detail that process here, but I will be happy to elaborate in another post if anyone is interested. Long story short: there are only 3 unused bytes in the Vista boot code and the code for programming the configuration registers need 17 bytes. Fortunately, the boot code also contains text for some error messages: "Invalid partition table", "Error loading operating system", and "Missing operating system". These seemed a bit wordy for me, so I changed them to "Bad partition table", "Bad OS", and "No OS" respectively. This freed up a whopping 47 bytes that I could use for additional code.

3. This additional space needs to be contiguous so I moved my newly modified text to the end of the MBR code and then modified the pointers used in the boot program so that it could still find them. This put some empty space in-between the actual boot program and the error message text.

4. After examining the original MBR boot code I decided that the best place to put the AHCI configuration code was at the beginning, before jumping into the standard boot program. This meant I had to move the entire program down 47 bytes, placing the empty bytes at the beginning of the file. This required changing a few pointers in the original code so it would still run properly, but I got it working with a minimal effort.

5. I then put the code for AHCI configuration at the start of the MBR file and filled in the rest of the space with 0x90 (NOP opcode for you assembly language programmers) so that it would run my code at the beginning and then continue right on with the standard boot code afterwards.

6. Then, I wrote the modified MBR to the disk:

- sudo fdisk -u -f ahci.mbr /dev/rdisk3

- again, make sure you use the correct disk where I have rdisk3 above

- Also, you have to use rdisk instead of disk so that fdisk can access the RAW drive

7. After that I was able to reboot into Vista using AHCI mode

 

Credit goes to pipomolo42 for the original AHCI configuration modification for GRUB. The code I used was blatantly taken from his GRUB patch file although I did verify it against the 631xESB/632xESB I/O Controller Hub Datasheet and I understand how and why it works now.

Also, I must give mad props to the guys at twocanoes, authors of the awesome Winclone utility for the methods used for reading and writing the MBR from within OS X.

 

For those of you who want to try this out, I see a couple of issues. First, I know that the Vista MBR is not the same as the XP MBR, so my modified one will most likely not work on XP. I'd be happy to attempt this on an XP MBR if someone can get me one. Second, I can't say for sure if all Vista MBRs are the same. I suspect that they are, but we would need to verify it. I know they are different for non-English versions of Vista because the error messages are different, but the actual code is probably the same. This is something else we would have to verify. Lastly, I don't know what the policy is for posting MBR code in this forum. What do you think, ludacrisvp? If it's allowed, I can post links to my original MBR (for comparison to yours) and to the one I have modified (for testing). I know that the AHCI code should work on Mac Pro models up through 2008 because the configuration registers are the same. I'm not sure what ICH the 2009 model has (is it ICH10?) but if someone can let me know I'll look into it. ICH10 should work the same according to the datasheet.

My next plan is to clean up the code a bit and then try my luck with getting this to work on my Santa Rosa MacBook Pro. In the mean time, PM me and I'll send you the MBR files I have so we can move forward.

If you need any additional detail on anything, let me know and I'll get back with an answer as soon as possible.

 

CK

 

EDIT:

The final 6 bytes of the MBR need to be copied over from your original MBR to make this work. This is because four of these bytes make up a disk signature that is stored in the Windows registry. If the signature in the MBR doesn't match the one in the registry, Windows will not boot. Thanks to mchaggis and ludacrisvp for pointing this out. They both noticed it when trying to use the modified MBR containing the signature for my disk. I was aware of this but didn't think about it until they pointed it out.

[fridgeymonster3]

@ludacrisvp... So, I'm too stuck at the find /boot/grub/stage1 command. I have a screenshot of gparted which I believe shows that I have a 200 MB partition at the beginning of the drive. Can someone please help with what the command line would be and whether my 200 MB FAT32 partition is on the beginning of the drive? Thanks!

 

[mchaggis]

johsock: yes the 09 Mac Pro does use ICH10 (http://www.intel.com/Assets/PDF/prodbrief/xeon-5500.pdf).

 

Is there a reason for having to do so much installing of drivers and restarting? Is it just because the Intel SMB driver comes as an app and will only install if it can see the correct device?

 

Looking forward to trying this

[johnsock]

johsock: yes the 09 Mac Pro does use ICH10 (http://www.intel.com/Assets/PDF/prodbrief/xeon-5500.pdf).

 

Is there a reason for having to do so much installing of drivers and restarting? Is it just because the Intel SMB driver comes as an app and will only install if it can see the correct device?

 

Looking forward to trying this

 

I checked the ICH10 datasheet and it should work just the same. I'm interested to see if you can get it working.

 

All the driver installing and restarting was partly due to the fact that I used the Intel installer app and partly because I was trying to be careful. We may be able to come up with a more streamlined approach (I have some ideas) once the MBR method is verified working for you. I listed the exact steps I took so that I could reproduce it.

 

Something else I thought of that I haven't looked into is installing Windows on the same drive as OS X. I'm not sure how this affects the MBR, but I'm going to look into it.

 

EDIT: I successfully patched the XP MBR to enable AHCI and was able to get it working on a Santa Rosa (2007) MacBook Pro with Windows installed on the same drive as OS X. The XP MBR had more free space available, so the patching was easier. Also, the driver installation was done with fewer steps this time. I think the easier driver install can be applied to Vista as well, but I'm going to test it out to make sure. I'll post results when I have them.

I'll post modified MBR files to the forum shortly. I'm waiting on some test results. If you want to try it out earier, PM me for details and MBR files.

[ludacrisvp]

I have tested the Vista loader modified MBR for Johnsock, I had to make some changes to his code so he will have to take a look at it to see why it needed to be changed to work for my Vista. We are hoping that it was just the difference because he is on original MP and I have MP 08.

 

Driver installation for vista is really actually only a 3 step process.

Change the registry key, reboot into OSX or Linux and flash the new MBR that he made,

reboot into Vista and run the installation application for the Intel Matrix storage drivers.

 

The forcing driver installs is only needed in XP because the registry cannot be modified to tell XP to look for AHCI mode controllers at boot.

 

@fridgeymonster3 - we are currently working on a better solution that will avoid the GRUB loader and extra partitions.

Yes, your EFI partition is the first one on the drive.

[mchaggis]

I got it working too, but using the 'original' MBR (good_ahci.mbr) from johnsock. I didn't do it exactly like in the post above though.

 

Comparing the MBRs from 3 different Vista installs on different disks (johnsock's plus 2 of mine: one Bootcamp with OSX on the same disk; the other no Bootcamp, straight Vista) I found they were identical with the exception of the final 6 bytes (0x0 to 0x1B7 were identical). So I dd'd the first 0x1B8 (440 bytes) of johnsock's code onto /dev/diskX, not rdisk as suggested - when I umounted the disk in question /dev/rdiskX was no longer available. Is there a way to dd onto a mounted disk in MacOS? It told me the resource was unavailable until I umounted it.

 

The first attempt gave a BSOD (but too fast to see the code). Before trying this I'd installed the AHCI driver as suggested. I then tried again with 'Last Good Conf' so the AHCI driver was no longer installed. This worked! It detected the AHCI devices at startup, then I loaded the Intel Storage Matrix driver and no complaints.

 

ISM when opened shows a tree for the AHCI device with all my attached SATA drives underneath it, including NCQ enabled. I'm going to try it on the other disk (MacOS + Vista BootCamp) soon, but I'm going to get a problem dd'ing to the active disk.

 

Is this why you use fdisk by any chance? If you're wondering, I used dd because I know exactly what it does - I wasn't sure if fdisk might try to overwrite the whole MBR with only 440 bytes of data and lose the bytes which seem to be unique per disk.

 

More to come...

[mchaggis]

It seems to be working on my main disk now too. The process was similar, but this time I tried not installing the MS AHCI drivers before laying the patch. This resulted in a BSOD (no driver, I presume). I then had to re-lay the original MBR, boot back into Windows and install the MS AHCI drivers (I did it only 1 of the 2 SATA devices shown, the one with my HD attached to it). Then I re-relaid the patched MBR, booted into Windows and it detected the AHCI device. From then on it was plain-sailing, I just repeated the process for the second SATA controller. For some reason my 09 Mac Pro presents a 2-port SATA controller and a 4-port SATA controller separately, which is why I had to do it twice.

 

For reference this time I laid the MBR patch using a linux LiveCD and dd. The patch was the 440 byte version I modified (by removing the last 6 bytes), rather than the 446 byte original patch from johnsock.

 

The main stumbling block seems to be Windows drivers, and getting everything set up in the right order so Windows knows to use the right one after you transition to AHCI mode.

 

Edit: I've since realised that the '2-port SATA controller' has not been picked up as SATA/AHCI, it still seems to be operating in legacy mode. I presume the original code was written to enable one device which controls all 4 internal HD ports AND the 2 optical ports on the older Macs; wheras Apple seems to have put 2 controllers on the 09 Mac Pro - one for the internal bays and one for the optical ports. That sound plausible? This probably contributed to my BSOD problems when I tried to install it the second time - I may have installed the MS AHCI driver on the wrong one of the 2 available ports on my first attempt.