Performance issues after installing a new HDD to a Power Edge 430.

Hello,

We have a PowerEdge 430. 2 SATA Hard Drives 2TB each, on a RAID 1 with a PERC H730 Mini Integrated RAID Controller 1 (Slot 0 and 1). 

Recently added 3rd Non-RAID SATA 6TB Hard Drive to Slot 2. Having a performance issues since.

Controller Firmware Version 25.5.9.0001

Controller Driver Version 6.604.06.00

Can you please help? TY