I'm installing Windows Server 2008 r2 on a Dell PowerEdge r710 and having the same issue. I just installed a DELL PERC H710 512MB 6GB/S PCI-E 2.0 PowerEdge RAID Controller VM02C W/ battery and set up 2 1 TB drives with RAID level 1 and have already initialized the drives. When I try to install the OS, the drives are not visible. Any info would be helpful. Thanks!