I would suggest looking at the websites ibuypower or cyberpower both of which allow you to pick and choose what parts you want it built with and from what I have come to understand they are both reliable. I have had a computer from cyberpower for about 2-3 years now and I'm still able to run games like skyrim maxed out and have encountered no issues with hardware being installed wrong. Ibuypower if I'm not mistaken is also one of the major sponsors for some of the mlg gaming circuits if that helps support their legitimacy. But from both companies you get to choose everything from the case up.