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How to enable AHCI in Windows 7 post install

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Ok, here's a link to a guide that explains how to enable AHCI in Windows 7 if it wasn't enabled at the time of install - http://www.ithinkdiff.com/how-to-enable ... stallation
There's even a registry entry file you can just download, double click and it'll do all the hard work for you.
This will then allow you to dual boot Win 7 and OS X.

Please note: Do NOT apply this if you've got Windows running of a RAID setup, you'll manually have to change between AHCI and RAID if want to dual boot OS X and Windows in this case.
 
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Good find. I was facing that same problem. I found instructions on Microsoft site. This looks better...
 
I'm getting NTLDR not found while selecting 7 in Chameleon?
But if I change to IDE there is no problem booting to 7

Any ideas?

Cheers

Peder
 
V. Nice, Thanks.
 
I tried this but it didn't help me.

The story is that I don't have AHCI in my bios.... also, when I was in the regedit, the value was already set to 0!
 
Interesting, I think that by the time you're trying out OSX86 on your computer you will probably be aware of and assuming the risk, that its most likely to cause issues and errors that require you to reinstall (in all likelihood a few reinstalls :crazy: ) if attempting a dual/multiboot.

That article would only apply if you're installing OSX on a separate drive and those steps would probably be required BEFORE attempting OSX installation which means you would be doing the install OSX on a new/separate drive seeing that you have to use GUID partitioning for OSX on intel computers and any previous windows installation would likely have been on an MBR partition... stating the obvious here, I know.....

However, if you're following the tonymacx86 iBoot guide (its like the best guide ever! :thumbup: :thumbup: ) for dual booting off the same HDD, then you should not have any of the issues which the article aims to resolve :D assuming you had set the bios setting correctly to begin with before attempting to install vista or win7.

IMO I think that if you want to make it easy going then follow the iBoot guide and dont rush it, undertake each step carefully as instructed. Try dual/multi booting later and off separate HDD's, also make sense if your OSX is on a seperate drive on its own, in case some does go wrong (because it will) you can still access the internet (by disconnecting the OSX drive and using only the windows/linux drive) for trouble shooting if you have only one computer. two cents worth of unsolicited thoughts....

If dual/multibooting off several drives then just follow the guide step by step (patience is a virtue in these things) and install windows first, and OSX last e.g. if installing linux as well, install windows first (easiest option), login to windows and make sure its ok, then do the linux installation, then lastly OSX and multibeast. With linux, install grub on the root linux partition (if in MBR).

I have no idea on other linux bootloaders as I only use Ubuntu... I tried it with OSX in my install but it didnt work but I was happy to note that IF it could work, without serious scripting, you can choose between 32 and 64bit kernel at the grub menu, I'll look into that later and see if its possible to use a custom grub entry to get it going in either option... food for thought...

Lets just say I know this from experience :geek: ... I've had my OSX86 for about two weeks and I'm loving it!!! I can now install it with my eyes closed on my desktop... but I'm also careful, I have a time machine back up, and a whole separate drive which works perfectly unplugged and unused as a back up! Just in case.... :ugeek:

The moral of this post is if you already have windows installed, and want to try out OSX86 you have to use a separate drive for OSX and fix the ACHI issue first, otherwise you should not encounter this issue.
 
have 3 separate hd's: bus 0 = osx, bus 1 = win7p, bus 2= xpp; bios set for osx drive boot first.
if you installed win7 prior to osx and did not have the bios set to AHCI you will not be able to boot into win7 again unless you change the bios back to IDE.
disconnect other drives and change bios to IDE. boot into win7
may need repair and restart.
download this file: http://www.ithinkdiff.com/wp-content/up ... 5/ahci.reg
for some reason it may end the file with .mp3. remove that extension (filename: ahci.reg)
double click and authorize add to registry
reboot and enter bios. change to AHCI
G to G

if you installed osx first (changed bios to AHCI) prior to win7 install this would not be an issue.

How to enable AHCI in Windows XP post install: WITHOUT FLOPPY DRIVE : EDIT (now that i have done this a couple times)
resource:
http://www.intelforums.net/showthread.php?t=444831
download the latest Intel Matrix Storage Manager (i used IATA89ENU.exe)
Procedure:
1. disconnect all drives except for winxp 2. set bios sata and alternate sata (gsata) to IDE mode 3. put winxp drive on alternate sata bus (for me it was a gsata on the gigabyte motherboard) 4. startup windows 5. expand and copy IaStor.sys file to C:\Windows\System32\drivers\ 4. launch .reg file to add to registry 5. restart into bios. 6. set main sata bus to AHCI in bios (keep xp drive on secondary bus) 7. startup winxp 8. i do not know a way to stop xp from auto installing the wrong driver, soooo ... go into device manager and expand IDE devices (unless you can get to it quicker than me :) ). right click and update driver specifying the location of your expanded Matrix Storage drivers 9. you will see it updated to AHCI in device manager 10. shutdown and change your xp drive to the main sata bus. 11. restart using AHCI in xp. -lifesaver over reinstall using f6 floppy!

no problem with triple boot (separate drives) from bios (or alternate bootloader) with access to all drives (osx.6.3/win7p64/xpp_x86)
only problem still with booting xp from chameleon. sees it, but get the dreaded top left cursor blink.

my setup:
i5-750/ga-p55a-ud4p-f8/gv-n250-1gi/corsair-xms3-ddr3-4gb/cm-hyper212plus/optiarc/3xWDsatas/antec-tp650/cm650IIadv/osx.6.3/win7p64/xpp-x86/DellUltrasharp/applekey-a1243
 
This is a piece of information I needed: thanks!
I still have a doubt someone may be so kind to clarify: I have one single disk with a double partition XPSP3_32/Win7_64 and a third partition where I'm planning to install Ubuntu (from what I've read, it would had been better to install it before OSX, but this is disk 0 anyway); I installed XP after formatting the disk as IDE from Bios, and blindly Win7 afterward; then I stumbled on OSX SL and installed using Bios AHCI through iBoot and Multibeast on a second disk: very happy! :thumbup:
Now to let Win7 boot from Chamaleon, I would possibly try this trick of Regedit the register, and installing the drivers in this partition; my question is:
can I leave XP32 as it is and boot from it switching back to IDE from the Bios?
That would be my preferred solution, since I seldom use it now, so I will end up setting the Bios to AHCI, boot drive from OSX and eventually from Win7/Linux; if I need to boot from XP, I'll go back to Bios and set IDE to select the boot from XP afterward, still from the Bios.
What do you suggest?
TIA

PS: I've done just that I described above, and it works! If I need XP I switch to IDE from the Bios and select the HD with the two Win versions as first in priority, and choose the old sys at start up choice...
 
No AHCI anywhere in my BIOS?

I'm at a loss here, gang. Got a Dell Studio XPS with Vista preinstalled on SATA0, and I want to install Snow Leopard on a separate drive SATA2. So step one: enable AHCI in my BIOS, right? But I have been through every single menu in my BIOS, and there is nary a mention of AHCI anywhere.

I have updated the registry as described here: http://support.microsoft.com/kb/922976
Doesn't change anything.

If I try iBoot-Supported with current BIOS settings, I get stuck at "Still waiting for root device" (and yes, my DVD drive is SATA). If I try iBoot-NVIDIA (my graphics card is "NVIDIA GeForce GT 220") I get "NVEnabler: DEBUG Model found: Unknown nVidia card". If I try iBoot-NVIDIA with the -x flag I get "Still waiting for root device".

I have done every recommendation in the troubleshooting post: viewtopic.php?f=3&t=524 including upgrading the BIOS to the latest available from Dell.

Still, the only somewhat-relevant BIOS setting I can find is Advanced Chipset Features > SATA Mode, which accepts only ATA or RAID. Some posts here and there casually mention using RAID instead of AHCI, and the wikipedia article for AHCI says that RAID mode "also enables AHCI", so I tried it, but the iBoot install still fails same as above, and moreover I can't boot Vista... when I try to boot Vista I end up at the Intel Matrix Storage Manager where it says RAID Volumes: None Defined, and then lists my two drives as "Non-RAID Disk". I have an option to "Create RAID Volume", which I guess I could do.. format my OSX destination drive as RAID0 and then try iBoot?? Does that seem like the right strategy?

And if so, how am I going to get Vista to work again afterward? Can I set my BIOS back to ATA after the OSX install?

BTW: before each iBoot attempt, I power down, unplug the Vista drive, and plug the OSX destination drive into the blue SATA0 port. So even with Vista completely out of the picture I can't get anywhere!
 
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