Depends on your the OVA template used and the hardware requirements:
http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/connection/9x/supported_platforms/9xcucspl.html
http://www.cisco.com/web/software/282074348/99143/CUC_9.1_vmv7_v1.5.ova.README.txt