Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

shah1

macrumors regular
Original poster
Oct 30, 2010
176
26
Hi guys,

As per the title, is it possible to install Windows 7 via Bootcamp onto a Transcend Jetdrive 128gb storage expansion card? Not sure if it is wise to run Windows off a SD card but have read in the reviews for this particular product of people doing just that?

Reason for this choice is because of it being the most cost effective - I have 2012 128gb MacBook Air, i5 and 8gb Ram.

Look forward to your replies. :)
 

yjchua95

macrumors 604
Apr 23, 2011
6,725
233
GVA, KUL, MEL (current), ZQN
Hi guys,

As per the title, is it possible to install Windows 7 via Bootcamp onto a Transcend Jetdrive 128gb storage expansion card? Not sure if it is wise to run Windows off a SD card but have read in the reviews for this particular product of people doing just that?

Reason for this choice is because of it being the most cost effective - I have 2012 128gb MacBook Air, i5 and 8gb Ram.

Look forward to your replies. :)

Yes, but not in UEFI.

I've the steps for a UEFI installation of Windows 8.1:

Connect external drive to Windows VM. You must have a Windows VM in VMware/Parallels/VBox, or a Windows PC. Any existing Windows environment will do.

What you need:
install.wim file (obtain this from your Windows ISO)

Open elevated cmd.exe (run as admin)

Note: All commands aren't case sensitive, including pathway to files.

Type diskpart
Type list disk
Take note of the disk you want to select
Type select disk 1 (if your disk is Disk 1)
Type clean
Type convert gpt
Type create partition EFI size=100
Type format quick fs=fat32 label=EFI
Type assign letter=S
Type create partition primary
Type format fs=ntfs quick label=W2G (or any other name you wish for label)
Type assign letter=E
Type exit

Open up File Explorer. In your C drive, create a new folder named WIN2GO.
Put the install.wim file in this folder

Back in cmd.exe:
Type dism /apply-image /imagefile:C:\WIN2GO\install.wim /index:1 /applydir:E:\ (this process will take quite a while)
Type E:\Windows\System32\bcdboot E:\Windows /s S: /f UEFI

Restart your entire Mac. After the chime, hold down Option and when prompted to select your boot drive, select EFI Boot.

Proceed installation normally.

After installation, install Boot Camp drivers. Feel free to trash the VM once you're done too.

For best results, use USB 3/Thunderbolt. If you don't have USB 3, use Thunderbolt. If you have neither, stick back to the internal drive :)
 

shah1

macrumors regular
Original poster
Oct 30, 2010
176
26
That's doesn't make much sense to me - forgot to say I'm new to all this Bootcamp stuff and not sure what Windows VM etc are. Also what is UEFI? Thought it would be straight forward to select which hardrive I want to partition going through the steps on Bootcamp?
 

yjchua95

macrumors 604
Apr 23, 2011
6,725
233
GVA, KUL, MEL (current), ZQN
That's doesn't make much sense to me - forgot to say I'm new to all this Bootcamp stuff and not sure what Windows VM etc are. Also what is UEFI? Thought it would be straight forward to select which hardrive I want to partition going through the steps on Bootcamp?

UEFI is the successor of BIOS, with supported for very large drives.

It's better to install Windows in a UEFI environment on a Mac, because a Mac is natively UEFI.

A Windows VM is a copy of Windows running as a virtual machine on a Mac, like through Parallels, VMware or Virtualbox.
 

laurihoefs

macrumors 6502a
Mar 1, 2013
792
23
That's doesn't make much sense to me - forgot to say I'm new to all this Bootcamp stuff and not sure what Windows VM etc are. Also what is UEFI? Thought it would be straight forward to select which hardrive I want to partition going through the steps on Bootcamp?

The short answer is, there's no easy way to make Windows 7/8 boot from an external drive or SD card.

Yjchua95s method is one option, and there are some other guides with slightly different ways, but none are as easy as installing Windows on an internal drive with Bootcamp Assistant.

UEFI is the successor of BIOS, with supported for very large drives.

It's better to install Windows in a UEFI environment on a Mac, because a Mac is natively UEFI.

A Windows VM is a copy of Windows running as a virtual machine on a Mac, like through Parallels, VMware or Virtualbox.

In what way is UEFI installation a better option than BIOS emulation (Bootcamp)? (Edit: Yes, it's the only way to boot Windows from an external drive, but you are making a much more general statement.)
 
Last edited:

yjchua95

macrumors 604
Apr 23, 2011
6,725
233
GVA, KUL, MEL (current), ZQN
The short answer is, there's no easy way to make Windows 7/8 boot from an external drive or SD card.

Yjchua95s method is one option, and there are some other guides with slightly different ways, but none are as easy as installing Windows on an internal drive with Bootcamp Assistant.



In what way is UEFI installation a better option than BIOS emulation (Bootcamp)? (Edit: Yes, it's the only way to boot Windows from an external drive, but you are making a much more general statement.)

A BIOS emulation environment can only work with MBR drives, and there are limitations on the max size of the drive and the number of partitions. UEFI removes that limitation and also removes any overhead that used to exist with BIOS emulation, because UEFI doesn't require an emulation layer.
 

laurihoefs

macrumors 6502a
Mar 1, 2013
792
23
A BIOS emulation environment can only work with MBR drives, and there are limitations on the max size of the drive and the number of partitions. UEFI removes that limitation and also removes any overhead that used to exist with BIOS emulation, because UEFI doesn't require an emulation layer.

Can't comment on the partition size limit, as I could not find info on the maximum supported Bootcamp partition size. The limited number of partitions can cause issues however, and needing to boot a third OS along OS X and Windows would be a good reason to use UEFI. Or booting Windows from an external drive, like you said.

But what overhead are you talking about? Is there a difference in performance, other than a slight difference in boot times? All that is being emulated is the boot environment, after that everything is running natively, so where would the overhead come from?
 

yjchua95

macrumors 604
Apr 23, 2011
6,725
233
GVA, KUL, MEL (current), ZQN
Can't comment on the partition size limit, as I could not find info on the maximum supported Bootcamp partition size. The limited number of partitions can cause issues however, and needing to boot a third OS along OS X and Windows would be a good reason to use UEFI. Or booting Windows from an external drive, like you said.

But what overhead are you talking about? Is there a difference in performance, other than a slight difference in boot times? All that is being emulated is the boot environment, after that everything is running natively, so where would the overhead come from?

The overhead comes from some limitations in graphics performance.

The GPUs used by Apple have EFI firmware flashed onto them. Using Boot Camp in BIOS emulation will require the GPU to also have a BIOS emulation layer in order to be seen by a BIOS installation of Windows, and that emulation does degrade performance.
 

laurihoefs

macrumors 6502a
Mar 1, 2013
792
23
The overhead comes from some limitations in graphics performance.

The GPUs used by Apple have EFI firmware flashed onto them. Using Boot Camp in BIOS emulation will require the GPU to also have a BIOS emulation layer in order to be seen by a BIOS installation of Windows, and that emulation does degrade performance.

Could you provide some sources for this?

AFAIK, any Video BIOS emulation is only done to get Windows booting. After the GPU driver is loaded, there is no difference between how Legacy ROM or EFI ROM cards work. There should be no difference in graphics performance.
 

soongsc

macrumors newbie
Jan 8, 2016
1
0
Hi, I was trying this running an XP VM. when I "list disk" three disks show up, disk 0 looks like the VM drive, disk 1 seems like some reserved partition of 2GB, disk 2 seems like the normal storage partition on the JetDrive lite of 120GB. I could clean disk 2, but could not "convert gpt" and tells me to select an empty MBP disk. Would appreciate some help.
 
Last edited:

Gjwilly

macrumors 68040
May 1, 2011
3,216
701
SF Bay Area
Hi, I was trying this running an XP VM. when I "list disk" three disks show up, disk 0 looks like the VM drive, disk 1 seems like some reserved partition of 2GB, disk 2 seems like the normal storage partition on the JetDrive lite of 120GB. I could clean disk 2, but could not "convert gpt" and tells me to select an empty MBP disk. Would appreciate some help.

yjchua95's method only works for installing Windows 8 and above.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.