Install windows on PC; boot from that HDD externally

[Corndog5595]

Hello smart people. I have a spare laptop and I would like to use that old computers HDD to boot windows on my Mac. I know it will run slow over USB in an external enclosure, but that’s fine.

Is it at all possible to install windows with the HDD inside the computer and then take it out and put it in an enclosure to boot it on my mac?

 

[old-wiz]

Windows has code that prevents it from booting from an external HDD. There are probably ways around it, but it's not simple. Depending on the version of windows you still need something to translate bios calls to EFI.

 

[Corndog5595]

Damn. Well, thanks for the response. I was hoping it would be as simple as it was for OS X. When I replaced my HDD, I was able to pop the old one into the enclosure and boot from it with rEFIt or Option Boot.

 

[shrakner]

Of course not. That'd be way too easy.

I don't know if this helps you or not, but when I upgraded my MBP's internal drive, I had a bootcamp install with Windows XP. Since I upgraded to Windows 7 for bootcamp at the same time I upgraded the HD, I wanted to keep the XP install intact just in case I needed it. I used Parallels to copy the old Bootcamp partition into a virtual hard disk which I then put on my external HD. If I need XP, I can have Parallels start the virtual machine off the external, and otherwise it's not taking up space on my main HD. Of course, I now can't run XP natively off the drive, but it is still useable.

 

[FourCandles]

I believe that you can boot Windows from an external, but only if you have Windows Vista or 7 and only from an eSATA enclosure....which is a lot of ifs and probably rules out most Mac/Bootcamp users.

 

[Corndog5595]

Of course not. That'd be way too easy.

I don't know if this helps you or not, but when I upgraded my MBP's internal drive, I had a bootcamp install with Windows XP. Since I upgraded to Windows 7 for bootcamp at the same time I upgraded the HD, I wanted to keep the XP install intact just in case I needed it. I used Parallels to copy the old Bootcamp partition into a virtual hard disk which I then put on my external HD. If I need XP, I can have Parallels start the virtual machine off the external, and otherwise it's not taking up space on my main HD. Of course, I now can't run XP natively off the drive, but it is still useable.

This sounds like a doable solution. I just didn’t want to eat up space on my HDD until I get a 500 GB Momentus XT.

 

[balamw]

This sounds like a doable solution. I just didn’t want to eat up space on my HDD until I get a 500 GB Momentus XT.

It won't be good for gaming, but you can effectively have a snapshot of the laptop at your beck and call. (Personally I prefer VMWare over Parallels, but then end result is the same.)

NOTE: You do need to decommission the laptop though when you do this or you may end up with both copies being de-activated. I did this with my last Dell and simply removed the HDD when I donated it.

B

 

[Corndog5595]

I wasn’t planning on gaming like this. Trying to game off of an external HDD would be torture. Trying to game on a virtual machine that is running off an external HDD would be even worse.

The only thing that would be worse than that would be running OS X off of 1 external HDD and then running the virtual machine off of another, lol.

 

[shrakner]

NOTE: You do need to decommission the laptop though when you do this or you may end up with both copies being de-activated. I did this with my last Dell and simply removed the HDD when I donated it.

I don't think this will be a problem- if I understand correctly, Corndog plans on putting the laptop drive into an external enclosure, cloning it into a Parallels (or VMWare) virtual disk, and then wiping the drive and just storing the virtual drive file on that disk. At no point would the same install be running from two machines, and thus it shouldn't be a problem. The only hiccup that may occur is that I know Windows 7 (and maybe Vista and XP, but I don't know) will probably notice it as a hardware change and may ask to be re-activated, but that shouldn't be a problem.

 

[balamw]

I don't think this will be a problem.

It wasn't necessarily aimed at the OP. Just a general warning to anyone reading the thread that when you make a VM out of a physical system you don't get a free license that can co-exist with the physical system.

B