Warning LEDs remain green on Samsung SSD 840 Pro while on the 850 pro they turn from green to orange when the disks are activities therefore focus 850 pro. The model Icy Dock MB994SP-4SB-1 SATA compatible LEDs with 840 pro.
If not unlike the model Icy Dock MB994SP-4SB-1, fans of this one are necessarily running of a drive is connected, the only way when you have ssd that do not require cooling is to disconnect, and then silence.
If it's hard disks then change for noctua 40mm 12V.