Unable create 64 bit guest in virtualbox running on Ubuntu Sever 17.04

I have a Hp dl360 g7 box which I acquired. I want to use as a lab machine, so I installed ubuntu server 16.04 and then upgrade to 17.04. My problem is that I have installed VirtualBox 5.2 on it, however, I am unable to create 64 bit guest machines despite enabling virtualization in my bios.

I have 2 Intel Xeon E5649 2.53Ghz installed
24Gb of Ram

Any Idea what am doing or did wrong.

I would really need so help as I have been several days behind in a number projects which I am depending of this machine to complete.

I’ve moved this to the https://community.ubuntu.com/c/support-help-requests category because this site isn’t designed to take tech support questions. Sorry. I’d recommend using one of the official support channels listed on the Finding Help page.