Thanks for the help!!!
I don not need graphics support
I do not know if is only on my enviroment, but, dynamic memory allocation does not work with those.
I mean, usually I setup an fixed memory value as default and an plus for when the server need, example:
DNS server using ZFS I set up 2 GB RAM as default
And setup plus 2GB as shared
So if my DNS server need more memory (avoiding swap) ESXi will increase the memory making the total avaliable 4GB on stress, and without load decreasing for the minimum 2 GB making that 2GB avaliable for other shared enviroments too.