Mobile/Portable Gaming Desktop PC Build

[Appser]

I want to buy/build a new gaming PC that should be portable between two places. The two "places" have both already their own monitor. I would like to build my PC around this case if it is possible:
http://www.corsair.com/en/graphite-series-380t-white-portable-mini-itx-case
My budget is set to a maximum of about 1100€.
I have had very good experiences with NVIDIA graphics cards and Intel processors so far and would really like to include them, especially 7th Generation Intel® Core™ i7 (even if it is extravagant).
Otherwise, I am open to suggestions of all kinds.
It would be my goal to play games like CS:GO on high settings with 100+ FPS and for example H1Z1 with playable Framerates.
I want to keep the PC min. 3 years and do not want to upgrade it in time.
I do not have a lot of "hardware computer skills", but I could imagine to build a computer myself (with the help of friends, parents or so ...). If this is inadequate, one would have to propose a finished PC.
I have an old PC to take parts out of it. Click here for more information:
Https://www.amazon.de/i5-4440-3-10GHz-GeForce-Windows-black/dp/B00OLL0MC0#productDetails
Thanks for your advice and suggestions

 

[Appser]

And I have an extra question: Should I overclock my PC then? When not, then why should I not do it?

 

[Deadpool]

https://de.pcpartpicker.com/list/HmdZGf

You should OC if you feel your components are not up to the task you want them to be. Example: I want to play FO4 at 120FPS on 1440p with my 1060. If I´m getting only, let´s say 100FPS, I´ll OC and get those 20 extra FPS. Otherwise you shouldn´t do it.

It´s $30 over budget. If you don´t want to pay that extra you could make some modifications to make it fit. By the way, I7´s are not necessary for gaming, an I5 will do perfect.

Oh I see you already have an HDD. In that case you are not over budget. Just ignore that.