http://gitlab.cloudforms.lab.eng.rdu2.redhat.com/cloudforms/cfme/merge_requests/566
Root cause was having a VC >= 5.0 and VMs on hosts <= 4.1. The numCoresPerSocket property was added in 5.0 [1] so the VC just set that value to 0 for any hosts older than 5.0. [1] https://www.vmware.com/support/developer/converter-sdk/conv55_apireference/vim.vm.VirtualHardware.html
Verified w/ 5.1u3 Server Name EVM Version 5.4.5.2.20160315175001_800759c User Name Administrator User Role EvmRole-super_administrator Browser Firefox Browser Version 38 Browser OS Linux
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHBA-2016-0171.html