MTRRs error on installing esxi5.5 within virtualbox

Hi Guys,

I encountered an MTRRs error while I was trying to install esxi 5.5 within a VirtualBox (ver 4.3.20) which runs on CentOS 6.6.

The vbox settings are:
        Type: Linux
        Version: Linux 2.6/3.x (64bit)
        RAM: 4096MB
        CPU: 2core

The iso was bootable, but hanged with purple screen and mentioned about: No variable MTTRs: assuming ESX is running in a VM.

How can I get rid of the problem? Thank you!