Help an old man make his son a twitch streaming machine for consoles - please (and thank you!)

Build Help/Ready:

Have you read the sidebar and rules? (Please do)

Yes.

What is your intended use for this build? The more details the better.

This is for my son. I have built many an older PC but now he is talking about stuff I don't know about. He wants to be able to stream to Twitch at 720 or higher from his XBox One using an ElGato (the cat??) and OSB.

If gaming, what kind of performance are you looking for? (Screen resolution, FPS, game settings)

Not for gaming as he is using his xbox for that.

What is your budget (ballpark is okay)?

I would like to keep this between 500-600 if at all possible as he has saved up $400 but my research says we are going to need more to make this work.

In what country are you purchasing your parts?

USA

Post a draft of your potential build here (specific parts please). Consider formatting your parts list. Don't ask to be spoonfed a build (read the rules!).

This is where I start to draw a blank. So much has changed since my last PC build (early 2000). Anyway, here is what I have come up with so far:

• i7 processor because what I read says that streaming can use hyperthreading - is this true or could a i5 do it?
• 8+ GB of RAM (but what speed?)
• Onboard graphics is fine because he doesn't do anything other than run the streaming software and the hardware
• Harddrive (100 GB+?) - Can this be an old fashioned RPM drive or should it be the newer SSD?
• Any generic case will work that has a power supply to support it.
• No monitor, keyboard, or mouse needed.

Provide any additional details you wish below.

I know the above isn't exactly a good list and I am not trying to be "spoonfed". Here are some of the builds I was looking at to get a reference (there are just too many options these days - lol):

https://www.reddit.com/r/Twitch/comments/2qf47s/cheapest_pc_desktop_for_twitch_streaming/

http://pcpartpicker.com/user/UltimaN3rd/saved/bGZG3C

http://www.newegg.com/Product/Product.aspx?Item=N82E16883229563R

I know this probably isn't much, but I really appreciate any help and pointers you can throw my way. He currently is using his laptop but its just not enough power and he says he is experiencing lag. Our internet is Comcast and about 50 down with about 9 up according to the speed test website.

NOTE: You do not have to follow this format, but please be sure to answer these questions. Please do not ask to simply be given a build. You are welcome to delete this section.

Submitted by mx_Seattle Xbox 720 Release Date 2015