My son is wanting to build a gaming PC from scratch. I currently have a hp P6653w which is 6 years old. I was wondering if there is any parts from it I could use in the build or if there are any possible upgrades I can make to it to improve performance. He would probably be able to spend max 700 on his build. He currently has xbox one and ps4 but he met a friend of mine who is big into PC games and now he wants to go that way. Help please I am clueless about where to start. Thanks for any suggestions