Try to use HP customized ESXi images for ProLiant
http://h18004.www1.hp.com/products/servers/software/vmware/esxi-image.html
This problem occurred may be because you have Dynamic Smart Array B120i
But with HP image it should be work.
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?objectID=c03871499
BR, Oleg.