Here are my power numbers under FN
Setup
C226 board
1x 8gb DIMM w/ ECC (set to 1.5V)
G3220 Pentium
Stock Fan set to 50%
Dell RM112 power supply
Single WD Green 1.5 TB drive
IPMI connected and enabled
1 NIC connected and enabled
Disabled stuff in bios:
-USB3
-Serial port
-Enabled platform C state support
-Disabled virtualization Support
Drive at idle: 21.3W - 21.5 W
Drive sleep: 19.1W - 19.5W
CIFS share transfer from another system to this drive in stripe at ~80mb/s (limited by drive speed) 33W - 34W
Drive disconnected: 18.5W - 18.9W
-----Note the platform has itermittant spikes to ~28W at idle, then settles to ~19.8W then down to 18.5W. I suspect this if Freenas doing something
These numbers represent my Kill a Watt, and my extremely efficient PSU, so don't expect to reproduce.
I will compare with Windows 8, ESXi and NAS4Free later.
A gripe I have is there is no under-clocking support. I wish I could cap CPU speed at 2.0 GHz or so.
My old MSI H61 board with a Sandy Bridge Pentium idled ~3W lower, but of course I was only running 2gb ram, single NIC and no ECC, no IPMI, etc....
Other performance info...
I have a 6x toshiba 7200 array in RAID z2... scrubs come in at over 600mb/s on 3.5TB of data. CIFS is about where expected at ~100mb/s.