Asus 1U Rackmount Chassis Kit R10-A2P4 - Manual (Page 30)

Chapter 2: Hardware setup 2-18
2.7 SATA backplane cabling
Ensure that the FAN1 connector on the SATA backplane and the
CPU_FAN2 on the motherboard are connected via the 3-pin fan cable.
The fan RPM (rotations per minute) are monitored and automatically
adjusted through this feature.
Connect the SATA
cables from the MB
Connects the SMBus
cable from the MB (FAN1) Connects the fan cable
from CPU_FAN1 on the MB
Connect the system
fan cables
Connect the SATA HDDs
Connects a 4-pin plug
from power supply