This was built for a relative, and was originally going to be a simpler upgrade. I looked at their old computer, and I knew it was time for a serious upgrade. The CPU was stuck to the CPU cooler, because thermal paste had never been reapplied and nothing was ever checked. How the old build kept on running, I still don't know. Ask Forrest Gump? shrugs
Anyways, so we went with the AMD Ryzen 5 3600X, because I had heard about the next generation of AMD desktop processors releasing. The relative had an 10-11 year old AMD processor in the old desktop build that was working quite well, so it was easy to convince them to upgrade to the 3rd gen Ryzen series. The motherboard is an X570 instead of a B450, because I found out, after reading many articles, that X570 does in fact support 3rd gen Ryzen CPU's out of box, whereas B450 does not.
Once we picked out the case, we knew we wanted both an RGB cooler, and RGB RAM cards. The G.Skill Trident Z & Cooler Master Hyper 212 RGB Black Edition were easy purchases at that point. That particular cooler comes with an RGB switch (as does the case), that we ended up just not using. The RGB on everything is going through the motherboard and the power supply, because we didn't see a point in controlling the RGB through the case, if we couldn't control the colors from outside the case, so that's why we went that route. It was difficult to setup, but we eventually got it.
I already knew that the Cooler Master brand was reliable, but was debating between the MasterWatt 750W over a Corsair RM850x PSU. After doing more research, and seeing how Corsair has dropped the ball a little in terms of quality control, we went with the Cooler Master MasterWatt for the PSU. We could have gone with the 650W to save a few dollars, but 750W would future proof his setup for future upgrades.
They will be upgrading their GPU soon, as they plan to play more open world games for now, but this was a solid build, meant to last. With what's running in here, plus only having SSD's, it is literally the quietest build that I have ever heard (well, not heard I guess) running even AAA games.
EDIT: Hopefully upgrading the GPU to an RTX 2060 SUPER or RTX 2070 SUPER by the end of Spring... 2020. lol! :)