If you have some issues with HP ilo, you can reset it in command line. Just connect by SSH to ilo ip address and execute following command: reset /map1
ESXi 5.5 threw PSOD, Raid controller driver
I have received PSOD several times at diferent esxi hosts DL180 G6 (esxi 5.5 hp + applied all patches build: 1892794). There is a known issue with the hpsa driver that can cause PSODs, you should update to the latest scsi-hpsa 18.104.22.168 version.