Hello grabavozas,   The change is a destructive process. I'll link you to steps required: PowerEdge Server - How to Create Virtual Disk in eHBA mode for PERC 10 [URL] Caution: The data will be lost if clear all existing configuration, please backup the data in advance.  
Hello, is H740P controller RAID to eHBA mode change a destructive process? Will the controller keep my RAID1 and RAID0 virtual disks and does not mess Windows Server 2016 UEFI boot process on one of vdisks? Firmware, server BIOS is up to date. Thank you. [IMAGE]  
H740P RAID to eHBA mode change