Dell PowerEdge R410 User Manual
Information update, System fan noise
System Fan Noise
It is normal to experience substantial noise from the system fan4 under certain
operating conditions. The following BIOS message would appear on the screen
when the system detects a PCI-e card in the expansion slot.
"Fan 4 will speed up for PCI area cooling when a PERC
or 10GbE NIC card is detected."