Your HP server may runs fine on ESXi 4.x or 5.0, but you may get error message No NIC found with MAC address xx:xx:xx:xx:xx:xx after upgrade to ESXi 5.1 or later.
That’s caused by network adapter firmware, you have to upgrade server network adapter firmware by HP SPP 2013.02 or later. I would recommend you upgrade firmware of each component to this version, it’s pretty stable to run ESXi 5.1.
