This is more than a little annoying. After upgrading my VirtualBox to version 3.1.6, it now decides that my cpu’s AMD-V is not operational. Everything was fine previously, everyone played nice together. Now it refuses to start my 64bit guests.
From what I have read, previous versions of VirtualBox ignored the VT-x/AMD-V setting on my motherboard.
I had two servers which were affected.
Server1 Motherboard: Biostar TA790GX A2+ CPU: AMD Phenom X4 OS: Fedora 12 Bios: Virtualization Enabled
Server2 Motherboard: ASUS M3A78-EM CPU: AMD Athlon II X2 250 OS: Ubuntu 9.10 Bios: Virtualization Enabled
The workaround that I have found involves setting the following environment variable.
So I appended the following to my /etc/profile.
I logged out and logged in again and now things appear to be fixed. I am able to start and run my 64bit guests again.
UPDATE 05/08/2010: Part II: VirtualBox is giving me friction about AMD-V