First Build

Hello all,
I am looking to build my first FreeNas server. And wanted to get some feedback on the hardware config.
I basically went through the forum and used similar specs as other members. I haven't ordered any parts yet, but this what i was thinking:

MB/CPU = AsRock C2750D41 - This seems to be a pretty popular choice among the members.
RAM = 16GB (2x8) ECC Ram from Crcial CT2KIT102472BD160B
USB = Kingston DataTravler 100G3/16GB
Drives = 4 x TB WD RED NAS Drives (these i already have)
Power...

First Build