  One other thing, I'm assuming that this is a typo. These are SATA drives, correct? You stated that these drives were working previously in a RAID 1 in the same configuration. The S110 is a SATA controller, it does not support SAS. Thanks
Hello! I have just replaced the system board in our Poweredge and when I try to boot the system cannot detect any of the 2 x 1T SAS drives.  It only detects the NIC cards and the DVD drive.  They were previously set as a RAID 1 I believe. We have embedded RAID using the PERC S110.  When enter the PERC BIOS (CTRL-R), no physical drives are listed (just the DVD drive).  I'm pretty confident all the cables are connected properly; I'm not getting any errors on boot... I've tried BIOS and UEFI boot both with no luck.Any thoughts or things I can try? Thanks! AlexW 
Poweredge r420 replaced sysboard- now cannot see both SAS drives