Perfect build for streaming PC

[MikeGold]

Hey, I'm considering building dedicated machine for streaming. I don't want to use my main cpu power for that purpose. So what would You suggest partswise? It should preferably be mini/micro atx with a decent processor and some very basic GPU. I'm not sure how much ram, what PSU to pick and how not to go over the top with specs and price, yet to get some great results with real time encoding. I would like to find a good balance between price and efficiency. 

Thanks in advance for the suggestions.

[Bazilias]

What's your budget and where do you live?

[MikeGold]

Ireland. I won't spend more than 500 euro on it. I have spare GPU (Geforce 780ti).

[Terryv]

I assume you're using OBS for streaming?

 

You really don't need much power for the dedicated streaming machine. I'm thinking i3 (a pentium might also be enough) with 4gb ram a capture card for video pass through and integrated graphics will be fine. Also use Linux for reduced cost and hardware overhead.

 

If you're using relive/shadowplay, then you need windows and a GPU but you can cut back on the CPU

[MikeGold]

I'm using Xsplit. If Pentium was enough I would just use my main rig for encoding. I want to have a really good quality on the low bitrate that Twitch allows, which requires some computing power (I don't want to use Shadowplay). My current rig is: 
 

i7-4820K
32GB Ram
EVGA GTX 1080 FTW 

And on the maxed out Overwatch I can't stream with acceptable quality without little hickups in game.

 

[Terryv]

then an i3 or better is the way to go