As many of you may know, Sony has disabled hardware assisted virtualization on most, if not all, their Vaio branded laptops. This is a pain in the arse when you need to run programs which need hardware assisted virtualization like, VMWare, VirtualBox and Microsoft’s XP mode for Windows 7.

Here’s what I did to enable it (briefly):

  1. Make sure your CPU can actually support VT-x. Most Core 2 Duo and newer CPUs should be compatible.
  2. Created a bootable USB DOS startup disk.
  3. Added the SYMCMOS program to it.
  4. Booted into the DOS environment and ran the SYMCMOS program.
  5. Edited the outputted file. You have to find the register to edit and change the [0000] to [0001]. In my case, my Vaio was a CR353 so the register I had to change was 05BB. A comprehensive table of all the BIOSes of the Vaios can be found here.
  6. Saved the file back onto the NVRAM
  7. Reboot.

That’s briefly what I did to enable VT-x on my machine. You can find a more thorough guide



I can now virtualize 64bit OSes and run Microsoft’s XP Mode. Have fun.

Please note that although this shouldn't brick your computer completely (if it doesn't boot, just remove the CMOS battery for a minute and put it back in) but in the slight chance it does, I accept no responsibility for damages caused. Use at your own risk.