If you see my Gallery thread, you see my Solaris ZFS build. It include custom built Wood case with EMI shielding and modified powersupply, and custom HDD mouting.viewtopic.php?f=14&t=61190
The Fan speed is controlled by Mother Board BIOS, and runs at very low speed, and only increases to speed when CPU hits 55+c. which is never. Even with 2x Prime 95 thread, it does not budge 42c.
I also have one 120mm fan common for HDDs and MB and Powersupply. Original intent was to mount tower heatsink with only one fan total, but it became little tight to mount tower heatsink.
BTW, I run Ubuntu inside Solaris Express 11 using Vbox. This is to run MediaTomb upnp server. I tried coherence upnp in solaris, but lot of issues. But if you have success with coherence, let me know.
I have 6 x 2TB SATA drives, and 1 x 2.5: IDE drive, and flash drive for ZIL and running with 8GB memory. Running RAID Z2, one dedupe folder,and non- dedupe, all run compression.