Dual Booting SL + Windows on one Hard Drive

[ZackMacAttack]

Well the issue is found in the hard drive's partition scheme. Apple uses the GUID Partition scheme and Windows uses the MBR Partition Scheme. Now Windows will install on a GUID Partitioned hard drive but the Chameleon Boot Loader will not see the windows installation.

 

There are a few ways to booting with only one hard drive.

 

1. The first would be to Back Down to 10.5 (Leopard) and use a Distro like Kalyway. These distro's can be installed on a MBR Hard Drive.

 

2. The Second would be to use a Snow Leopard Distro

 

3. Another way is to Use the Windows Boot-loader to load both your hybrid MBR partitions for Mac and Windows Learn more about hybrid MBR/GPT HERE. You can use EasyBSD to edit the Windows boot-loader and add a Mac Loading option. (This is not the preferred method)

 

But the best way to dual boot is still to use two hard drives.

[srs5694]

To the best of my knowledge, Windows will not install to a GUID Partition Table (GPT) disk unless the computer uses EFI firmware rather than the more common BIOS. If you've found a way around this limitation, please post details. Many people have posted that Windows will install to GPT, but they've either never provided proof or they've turned out to be mistaken. The usual explanation, when they post details, is that they've got hybrid MBR configurations, in which a proper GPT configuration is modified in a standards-defying way to include up to three partitions in the MBR table. This works, but it's flaky and it often comes back to bite at a later date. Apple relies heavily on hybrid MBRs in its own Boot Camp, and Apple's Disk Utility converts a disk into a hybrid MBR whenever you create a FAT partition in Disk Utility, so it's easy for people to think they're running bog-standard GPT setups when in fact they've got hybrid MBRs.

[ZackMacAttack]

To the best of my knowledge, Windows will not install to a GUID Partition Table (GPT) disk unless the computer uses EFI firmware rather than the more common BIOS. If you've found a way around this limitation, please post details. Many people have posted that Windows will install to GPT, but they've either never provided proof or they've turned out to be mistaken. The usual explanation, when they post details, is that they've got hybrid MBR configurations, in which a proper GPT configuration is modified in a standards-defying way to include up to three partitions in the MBR table. This works, but it's flaky and it often comes back to bite at a later date. Apple relies heavily on hybrid MBRs in its own Boot Camp, and Apple's Disk Utility converts a disk into a hybrid MBR whenever you create a FAT partition in Disk Utility, so it's easy for people to think they're running bog-standard GPT setups when in fact they've got hybrid MBRs.

 

I am sorry. You are right the only way is on a hybrid MBR.

I currently have two hard drives in my HP DV7 Laptop and that is how i Dual boot.

[CurlyCarlos]

Netbookinstaller (primarily Chameleon with a few tweaks) does something, because I can partition my entire drive as GUID and give it two partitions, Snow Leopard will install and afterwards Windows doesn't see anything wrong with the drive.

[Mustang Sally]

To the best of my knowledge, Windows will not install to a GUID Partition Table (GPT) disk unless the computer uses EFI firmware rather than the more common BIOS. If you've found a way around this limitation, please post details. Many people have posted that Windows will install to GPT, but they've either never provided proof or they've turned out to be mistaken. The usual explanation, when they post details, is that they've got hybrid MBR configurations, in which a proper GPT configuration is modified in a standards-defying way to include up to three partitions in the MBR table. This works, but it's flaky and it often comes back to bite at a later date. Apple relies heavily on hybrid MBRs in its own Boot Camp, and Apple's Disk Utility converts a disk into a hybrid MBR whenever you create a FAT partition in Disk Utility, so it's easy for people to think they're running bog-standard GPT setups when in fact they've got hybrid MBRs.

 

 

GPT is only on 64 bit of win 7, i have a single hard disk with win 7 and osx 10.63-64. my system is a p5q pro with my modded bios using the alc1200 audio and onboard lan, sata drives, o/c 8500 with a 9800 gt starts and restarts 100% (don't use sleep so can't help there). i boot into my boot 132 disc use a usb retail of 10.60, go to disk utilities select GUID partition scheme, 4 partitions 2 for osx and 2 for win 7, format first 2 as msdos, other 2 as mac journaled. i then exited osx installer and boot into my win 7 install, select options and format the fat 32 partition that osx disk utilities made to NTSF.

 

configured win 7. i used my bootdisc to let me install my usb osx 10.6. i used myhack installer after to install Chameleon and dual boots perfectly. update to 10.63 with no problems

[ZackMacAttack]

GPT is only on 64 bit of win 7......

 

That make since now that i think about it. I have Windows 7 Ultimate 64-bit. You know Microsoft should just release one version that has both 32 and 64 bit. then the installer decides if you can have a 64 bit os or not. But I guess that is why OS X is the Most advanced operating system in the world. LOL!!!

[Mustang Sally]

That make since now that i think about it. I have Windows 7 Ultimate 64-bit. You know Microsoft should just release one version that has both 32 and 64 bit. then the installer decides if you can have a 64 bit os or not. But I guess that is why OS X is the Most advanced operating system in the world. LOL!!!

 

 

 

 

no that's why OSX needs a lameass dual layer disc and is larger than both versions of win 7 x86 and x64 combined (and why you need win to detect the hardware LOL!!)

[ZackMacAttack]

no that's why OSX needs a lameass dual layer disc and is larger than both versions of win 7 x86 and x64 combined (and why you need win to detect the hardware LOL!!)

 

Haha very true. O and speaking of large space on apple products, Logic Studio is 50 GB!!!!! O well.... I still LOVE OS X better then windows.

[srs5694]

Netbookinstaller (primarily Chameleon with a few tweaks) does something, because I can partition my entire drive as GUID and give it two partitions, Snow Leopard will install and afterwards Windows doesn't see anything wrong with the drive.

 

If you partitioned the disk using Apple's Disk Utility and created a FAT partition for Windows' use, then you've got a hybrid MBR, not a "straight" GPT. If you want to test my hypothesis, try using separate MBR-only and GPT-only disk utilities to examine the partition table, or use something that will let you independently examine both -- but especially the MBR side. For instance, in my GPT fdisk's gdisk utility:

 

# gdisk /dev/sdc
GPT fdisk (gdisk) version 0.6.7

Partition table scan:
 MBR: hybrid
 BSD: not present
 APM: not present
 GPT: present

Found valid GPT with hybrid MBR; using GPT.

Command (? for help): p
Disk /dev/sdc: 31576064 sectors, 15.1 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): D5EDEE3E-4DB3-4A2D-A2F8-ABC682AB790D
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 31576030
Partitions will be aligned on 1-sector boundaries
Total free space is 15921182 sectors (7.6 GiB)

Number  Start (sector)	End (sector)  Size	   Code  Name
  1			  63		 8388670   4.0 GiB	 0700  Linux/Windows data
  2		 8388672		15654878   3.5 GiB	 AF00  Apple HFS/HFS+

Command (? for help): r

Recovery/transformation command (? for help): o
MBR disk identifier: 0x110F00EB
MBR partitions:
Number	 Boot	 Start (sector)	 Length (sectors)	Type
  1						1		   31576063 	0xEE
  2					   63			8388608 	0x07
  3				  8388672			7266207 	0xAF

Disk size is 31576064 sectors (15.1 GiB)

 

I ran this under Linux, but it would be exactly the same under OS X, except that you'd use a different device filename (perhaps /dev/disk2 rather than /dev/sdc). Note first the "partition table scan" near the top, which identifies the MBR as "hybrid." This would read "present" on a GPT-only disk, or "not present" (with "MBR only" on the "MBR:" line) for a straight-MBR disk.

 

Reading on, this output shows the GPT partitions (via the 'p' command), and it shows the MBR partitions (via 'o' on the recovery & transformation menu). The key is that partitions exist in both tables, and in particular, the MBR table includes both a type 0xEE partition (known as an "EFI GPT" partition, which serves as a flag that the disk has GPT data) and regular partitions (type 0x07 and 0xAF in this example). On a standards-compliant GPT disk, the MBR will contain only a single 0xEE partition that spans the entire disk.

 

See the Wikipedia entry on GPT for the technical details of GPT's structure. Note also that hybrid MBRs violate the GPT structure. They work because most OSes are fairly lax about enforcing certain GPT rules; Windows treats hybrid disks as being MBR disks, while OS X and Linux treat them as GPT disks.

 

GPT is only on 64 bit of win 7, i have a single hard disk with win 7 and osx 10.63-64. my system is a p5q pro with my modded bios using the alc1200 audio and onboard lan, sata drives, o/c 8500 with a 9800 gt starts and restarts 100% (don't use sleep so can't help there). i boot into my boot 132 disc use a usb retail of 10.60, go to disk utilities select GUID partition scheme, 4 partitions 2 for osx and 2 for win 7, format first 2 as msdos, other 2 as mac journaled. i then exited osx installer and boot into my win 7 install, select options and format the fat 32 partition that osx disk utilities made to NTSF.

 

Please check Microsoft's GPT FAQ for information on GPT support in various versions of Windows. The FAQ only covers through Windows Vista, but AFAIK Windows 7 acts just like Windows Vista. According to that document, there are 32- vs. 64-bit differences in Windows XP and 2003, but not in Vista. I can confirm from my own tests that 32-bit Vista as well as both 32-bit and 64-bit Windows 7 can read GPT disks, and that none of these editions can boot from pure GPT disks on a BIOS-based system. I've seen some reports of interactions between the bitness of Windows and the bitness of the (U)EFI implementation on (U)EFI-based computers, but I've not looked into this in any detail.

 

If you think I'm wrong about this, please do some tests and post the results. I'd love to know of some workarounds to get Windows booting on pure GPT systems. (I do know of the possibility of using UEFI DUET, but that's hard to get working.) There's a lot of misinformation floating around about this, probably because it's a complex topic and it's easy to draw the wrong conclusions if you don't look at it in enough depth. It's easy to overlook hybrid MBRs, to remember Windows XP rules and think they apply to Windows Vista or Windows 7, or to misattribute a change in behavior to an upgrade in your Windows version. Every major player in the game -- mainly Apple and Microsoft, but also Intel and various BIOS manufacturers -- has contributed to the confusion in one way or another.