This thread is meant to replace the now outdated old one about recommended controllers, these are some controllers known to be generally reliable with Unraid:   2 ports: Asmedia ASM1061/62 (PCIe 2.0 x1) or JMicron JMB582 (PCIe 3.0 x1)   4 ports: Asmedia ASM1064 (PCIe 3.0 x1) or ASM1164 (PCIe 3.0 x4 physical, x2 electrical, though I've also seen some models using just x1)   5 ports: JMicron JMB585 (PCIe 3.0 x4 - x2 electrically)