Restart or power the server on, press F9 after it asks you options there press F8 for ILO.
in that ILO menu you will able to find IP address assigned.
below links helps you to find the IP
http://h20000.www2.hp.com/bizsupport/TechSupport/Document.jsp?prodSeriesId=397989&objectID=c02985088
http://808techblog.com/2009/08/configure-hp-integrated-lights.html
Thanks,
Dileep