Kind of learned this the hard way, but when you kickstart a machine for CentOS 7, 1GB of RAM is not enough.
A default install on VMware workstation only assigns 1GB of RAM on a CentOS VM
But on an ESXi host it assigns 2GB
Originally I did not think this would be a problem because I have installed CentOS with 512GB, but looks like it needs 2GB when doing a PXE boot.