Option 1: Replace the Delta PFC0812DE fans with something that spins slower like the 6000rpm model.

Drawbacks: Substitute fans are pricy. Slower fans will have less airflow. Anecdote of MD1200 throwing faults if the fan is too slow. The SC440 and the MD1200 take up 4U and 2U respectively.

The clincher is not the technical issues. Rather, it is how much rack space the SC440 and the MD1200 are occupying. Good thing I have another R510 with 8 drive bays. Before we jump into it, there is another hurdle.

R510

1x Xeon E5630

4x 2GB RDIMM

PERC 6/iR

The PERC 6/iR's LSI 1078E controller does not support IT mode. Even if I flash it to LSI firmware, IT mode will not be available. I spent 1 week researching my options.

There are plenty of people who replaced the PERC 6/iR with the PERC H200 flashed to LSI IT mode firmware. I can do that too, but the PERC 6/iR uses SFF-8484 "wide" connectors and the H200 uses SFF-8087 connectors. I would need to replace the cables, and they don't come cheap.

Looking for ways to reuse the SFF-8484 cables led me to the SAS 6/iR with the LSI 1068E controller. The LSI 1068E is compliant to the SAS 3Gbps standard which has 2.2TB limit. My array has 2TB drives. Perfect.

The SAS 6/iR is cheap. Like $6 cheap on eBay. Googling for cross flashing the equivalent LSI 3081E-R IT mode firmware on the SAS 6/iR turned up exactly one result. Given how inexpensive the part was, it was worth the risk. I won't bore you with the technical details but the flashing was successful.

Moved the HDDs and SSDs from MD1200 to R510's hot swap bays and the USB flash drive from the SC440 to R510's internal USB port. Turned on the R510 and reconfigured the network, and FreeNAS is ready to serve again.

The R510 is much quieter than the MD1200. iDRAC6 reports power usage between 120 and 

New Storage II

R510 8 LFF bay chassis

1x E5630

4x 2GB RDIMM

SAS 6/iR flashed to LSI 3081E-R IT mode firmware

6x 2TB HDD

2x SSD for L2ARC and ZIL

The MD1200 and LSI 9200-8e will standby until I outgrow R510's 8 drive bays.