Run 64bit OS in Virtual Box from 32bit Ubuntu

Is it possible to run Windows 7 64 bit from a 32bit ubuntu OS?

I can reinstall Ubuntu as a 64bit OS, but would prefer not to if it is not necessary.

Solution 1:

From VB help:

VirtualBox supports 64-bit guest operating systems, even on 32-bit host operating systems, provided that the following conditions are met:

1.-You need a 64-bit processor with hardware virtualization support (see Section 10.3, “Hardware vs. software virtualization”).

2.-You must enable hardware virtualization for the particular VM for which you want 64-bit support; software virtualization is not supported for 64-bit VMs.

3.-If you want to use 64-bit guest support on a 32-bit host operating system, you must also select a 64-bit operating system for the particular VM. Since supporting 64 bits on 32-bit hosts incurs additional overhead, VirtualBox only enables this support upon explicit request.

On 64-bit hosts (which typically come with hardware virtualization support), 64-bit guest operating systems are always supported regardless of settings, so you can simply install a 64-bit operating system in the guest.

Solution 2:

For Virtual Box, here's the Virtual Box FAQ:

Note that VirtualBox also supports 64-bit guest operating systems, under the following conditions:

• You need a 64-bit processor with hardware virtualization support (VT-x or AMD-V)
• Since version 2.1.0, you can run 64 bit Guests while running a 32 bit Host.
• You must enable hardware virtualization through your BIOS

So it depends on your CPU. Just having a 64-bit processor isn't sufficient, the CPU also needs hardware virtualization support.

As an example, the Intel i3 540 is listed as having "Intel® Virtualization Technology (VT-x): yes", so it should work there.