Upgrading from RAID1 to RAID5, possible?

Dear all, I manage a HP Proliant ML 350G6 running Windows Server 2008R2 with over a 79Gb RAID1 (2 * 79GB).

Is it possible to move from the current Raid1 to a Raid5 without lossing any information/reinstalling the server?

Thank you

Paulo Magalhaes