Just reviewed what we discussed earlier. YOu stated that you had it connected to the SATA port on the motherboard. With the mini you will need to move that cable to SAS A over near where the mini card was connected. You will see SAS A silkscreened next to the port. SWitch the cable to there and check if the drives are visible. 
hello, i've bought a mini H310 for my poweredge R420 but i'm not able to configure the array because there aren't physical disk viewed by the controller. There are 4 cabled SATA discs .. The doubt is that the H310 will not works with cabled drives and perhaps is necessary a backplane? Thank you for helping
PowerEdge R420 - Integrated Perc H310 Raid not finding drives