its a fine machine, but for BF1 I do recommend a GPU upgrade.
that i5 will do you good for anything upto a gtx 1080 so don't worry about that.
other games like overwatch will run great on that pc.
if you've not brought it yet then I do recommend getting a different power supply
that would be fine, but I recommend this one
http://www.ebay.com.au/itm/6FT-1-8M-Displayport-DP-Male-To-DVI-D-Male-Adapter-Cable-Core-Cord-New-/361718497669?hash=item54381a4185:g:g10AAOSwOdpX0BLp
but the answer to your question is yes, you can get a cable but I do recommend a adapter and then...
You should be fine with 2x2gb ram, as long as you get a speed your mobo supports then its just plug and play.
this should do good: http://www.newegg.com/Product/Product.aspx?Item=N82E16820159021
also, your not the nicest child or person.
well I've just bit the bullet and am going to get a asus x99 deluxe 2...
also I've based most of my opinions on pricespy reviews, I live in new zealand and don't use amazon or new egg.