24/7 DLNA Server build

[Zonus]

For a couple of years I've fantasized about building a Media Server/NAS hybrid and I've been looking around for cheap ways to do it. I've considered using an old laptop and just run a Plex server, since they're super easy an simple but the only laptop I have laying around to spare is a Netbook with 1 GB RAM and a single core Intel Atom CPU. So I'm kinda planning out what I should do for a proper lightweight media server.

 

This is what I have so far:

• Cooler Master Elite 110
• ASRock H81M-ITX
• Pentium G3258 3 MB
• Corsair SF Series SF600 (80 PLUS Gold)
• Crucial Ballistix Sport 2 x 8 GB
• WD Red WD30EFRX 3 TB
         Total: 500$

 

I'm not very experienced when it comes to server builds so I'd like to know if I'm doing anything wrong here. I've kinda followed the FreeNAS recommended specs, and put in a 80 PLUS Gold PSU for 24/7 operation. I build my brothers and father PC's with Crucial Ballistix Sport (8GB in their builds) and I haven't had any problems with them. In fact I've had more problems with my Corsair sticks than any Crucial ones. The Pentium G3258 is running in my dads PC and it performs super well for the price. I'm wondering if there are any other viable alternatives? Could a Raspberry Pi 3 Model B be a cheaper alternative?

 

For OS I might install FreeNAS+miniDLNA, or simply go Ubuntu or even Windows 8.1.

 

I'd like to keep the project at around 500$ - 550$