I have an HP pavilion g7 running windows 7 64 bit. I have 3.48 gigs of usable ram and 185 gigs of free hard drive space. I downloaded oracle's virtual box for windows 7 64 bit and Ubuntu 12.04 64 bit. When I open the virtual box to install Ubuntu it says it needs an x86-64amd CPU but it detects an i686 CPU and won't continue with the install. If my hardware meets the requirements I don't understand why it won't install... Any suggestions?
It's because Virtualbox is not using hardware virtualization, without this it can only present a basic 32-bit CPU to the virtual machine. In order to allow virtualbox to present a 64-bit your CPU, select the virtual machine in the VirtualBox Manager, click on "settings", then select the "system" category (on the left), then go to the "acceleration" tab (last one), and ensure "enable vt-x/amd-v" is both enabled and ticked.
If it's not tickable (i.e. greyed out), that means your CPU's virtualization support is disabled. Enable it in your system's BIOS settings and try again.