windows 7 - How to check if Win 7 disk is 64bit and what version?

I've got a DVD that I've burnt from an MSDN ISO. I'm not entirely sure if its Windows 7 64bit or 32bit.

How can I be sure?

Answer

Quickest way is to go to the drive root. If you have a file named Bootmgr.efi you are running a X64/64-bit version.

Next way is disk size, the x86/32-bit version comes out at ~2.32GB whilst the x64/64-bit version comes out at ~3.0GB.

Lastly, you can go to the drive root and open the autorun.inf file.

In notepad, the 64 bit version shows:

[AutoRun.Amd64]
open=setup.exe
icon=setup.exe,0
[AutoRun]
open=sources\sperr32.exe x64
icon=sources\sperr32.exe,0

The 32 bit version shows:

[Autorun]
open=setup.exe
icon=setup.exe,0