solved due to some  racks troubles
hello i have an R920 4CPU with a RAID1 hdd build-in configuration. 2 600 GB hdd. I wish building an RAID6 with 4 600 GB hdd. I installed 4 another hdd but the Perc raid utility don't find the new hdd. have you got an idea ? thank you    
dell R920 and perc 730P