Ok everyone here we go. Just ordered all of this
CPU: Intel Xeon E3-1225 v3
Cooler: Artic Alpine 12
MB: ASRock C226M WS
RAM: A-Tech 16GB 2 x 8GB PC3-12800E ECC Unbuffered UDIMM DDR3-1600 Server Memory RAM
Case: Cooler Master N400
PSU: Corsair 750 power supply (already had from old build)
Ok what does everyone think? Give me some pointers on what I am missing or messed up. 
Looks fine. What will it be running? Unraid? Might need an HBA for your HDDs.
Either UnRaid or TrueNAS haven’t decided yet. I was thinking I could just use the SATA ports on the board but am I thinking incorrectly?
Have you used your SATAs or you have to invest in HBA?
how many hard drives and will one be a dedicated cache drive?
I think for either unraid or trueNAS you would get better performance with a cache drive.
I’m planning on a 128gb ssd as my cache drive - but mostly becasue I have one sitting. Even if I didn’t I’d probably buy one and would maybe aim at a 256gb. Mine will be SATA connected by the way
You have to answer the question, how much of docker and VM data are you going to store on this cache and how big are your files you are going to copy to your array
Well you use as much as fits. But at the moment I don’t know I have any files over 32gb. Then I see little reason to hold any cache VM data over 8gb. I don’t figure you nees to cache more than memory allocated
Either way figure having one is needed