SORRY for the long posting but you do need to read it all.
I am not making fun of you but I am curious as to how you come up with this list of parts AND get windows 10 free ?
If a so called pal or a small shop wants to build it for you at only 500 ( I take it that's £ ) and give you a FREE windows 10 package my advice would be to walk away. The reason I say this is because a not very tech pal who was a student got talked into a deal that was too good to be true but sadly he fell for it. He brought his pc round to me because he knows I am geeky. The upshot was every time he turned the pc on he got a message " you appear to have an illegal copy of windows" , the end result was he was able to use the pc after deleting the message and use his music writing software BUT nothing else.
Another indication that something was not right was it was supposed to have an ssd drive but the pc was very noisy , note , ssd make no noise. belarc advisor software scanned and confirmed it did not have an ssd.
I then had to tell his parents sorry but your son has been ripped off.
I often wonder if a racket was going on at the university because not long after his laptop was stolen a guy "just happen" to be selling students pc's at very special prices and guess what when **it hit the fan they vanished.
Ok so that's the warnings so now the sensible bit , if you are unfamiliar with pricings their is no way you will get a pc capable of even playing low spec games for only 500.
My final advice would be , you know what games you want to play so google the games for require spec to run them .
FOOTNOTE . for legal reason if a "company/small business" is offering to do everything for 500 DO NOT name them here just say yes or no to my question.