Good news overall. Lack of "official" Nvidia support is somewhat concerning, but don't count AMD out, they also make some very good cards. I've built plenty of gaming PCs, and have used cards from both manufacturers quite successfully - I generally buy whichever card is the "best bang for the buck" at the chosen price-point at the time, and surprisingly it isn't always Nvidia despite the considerable gamer-fanboy-bias towards the brand. My current rig has an 8gb AMD r9 390 (to which I added an after-market liquid-cooler) that allows me to game stereoscopically very well with games using massive amounts of VRAM (FO4, for example, routinely eats up more than 7gb of VRAM with all the high-quality texture mods that I use). At the time it happened to be the best bang for the $$$ I was willing to spend, and having 8gb of VRAM turned out to be a huge advantage as I'm not lagging while the system swaps textures in and out between VRAM and system RAM. If I was building this rig today instead of more than 2 years ago (or, when I upgrade the video card) there is a very good change I would end up going Nvidia, but I would certainly give both manufacturer's cards a look before deciding.
