Digital Storm Vanquish 4 Level 1
If customization is the most important thing to you in a new gaming unit, then consider a company like CyberPowerPC or Maingear. But for a straightforward gaming computer that requires no additional work to setup, this is a great option. It comes with an Intel i5 quad-core CPU and 8GB of DDR4 RAM. You also get an NVIDIA GeForce GTX 950 2GB video card and a 1TB hard drive for storage.
While Digital Storm does offer some upgrade options on this computer, most of them are external components like keyboards and monitors. If you want to control every single piece of hardware that goes in the case, then this option really isn't for you, though there is plenty of room in the tower for you to change components or add some yourself. Digital Storm does offer different Levels on their computers, with higher levels offering better components (but naturally also cost more). If your budget allows for it, take a look at level two, three, or four of the Vanquish 4 for systems that offer solid state drives, more memory, and more powerful video cards.