I was lucky enough to get my hands on a reviewers sample of this card through a friend of mine that has "connections." I was fortunate enough to be able to install it and benchmark the card on both a Z170 i7-6700K system and my personal X99 i7-5930K system, and was able to benchmark/or test every DX12 game currently on the market such as Hitman, Ashes of the Singularity, Quantum Break, and Rise of the Tomb Raider. For me, DX12 performance is the MOST important area of focus, especially for Nvidia since AMD has and continues to dominate its Nvidia counterparts at every price tier in DX12...in fact, Nvidia cards have actually displayed performance loss in switching from DX11 to DX12, and with the controversy surrounding Nvidia's Maxwell architecture (900 Series cards) and their complete inability to perform asyncronous switching at the hardware level, DX12, in my opinion, is where the GTX 1080 had to prove itself. The majority of new AAA PC game releases will quickly become DX12, especially since Xbox One has already fully implemented it, and because DX12 is such a superior API and places in the hands of the game developers the responsibility of ensuring games perform up to par on a piece of hardware, the performance of a given game on a given GPU isn't dependent on the GPU manufacture's ability to create perfect drivers anymore. What this means is that Nvidia's advantage in DX11 performance, largely because of their ability and budget for creating drivers, is no more, and AMD's former disadvantage will disappear as well. Now, the onus is on the GPU hardware to perform and not the programming. DX12 performance becomes even more important when you consider the rather expensive price on this card and that it factors into the desire to get as much use out of it as one can for as long as one can, preferably at least two years, so while DX12 might not be the sole API currently, sooner than later it will, and the GTX 1080's performance in DX12 will determine its life expectancy.Unfortunately, I have to report that the GTX 1080's performance in DX12 is, for lack of a better word, embarrassing, especially at 4K where one would expect this card to be able to perform and maintain at the least 60fps @ 3840x2160 resolution. Not only does it not achieve the necesssary 60fps, but the performance gains that the GTX 1080 obtains in the switch from DX11 to DX12 hovers around an average of a few percentage points, literally (the biggest improvement being about 3% now that I recall). What's even more disappointing is that the GTX 1080 only manages a few FPS more than the AMD Fury X in DX12 @ 4K. In fact, in Ashes of the Singularity, the GTX 1080 only manages 53.3FPS while the Fury X achieves an extremely close 49.0FPS. Again, in Hitman, the GTX 1080 achieves 47.0FPS and the Fury X 44.2FPS! To me at least, this is unacceptable on nvidia's part, especially considering that the GTX has an inherent advantage over the Fury X in that the former is produced on the 16nm node, while the latter is on the now relatively old 28nm process. Additionally, Nvidia had plenty of forwarning about DX12 and AMD's considerable advantage as a result of the hardware's ability to do asynchronous compute, so it's not as if Nvidia was caught off guard or blindsided; they've known for plenty of time that it is a big deal. I've attached a chart with a few examples of the GTX 1080's DX12 performance, and while some of you may look at the results from Rise of the Tomb Raider and say, "Hey, the GTX 1080 did a lot better than the Fury X in that game"...well, while it may be true on the surface that the GTX 1080 did considerably better in RotTR, an important consideration has to be pointed out in that at the last minute, prior to that game's release, Nvidia had the developers remove the use of Asynchronous compute, which while making the GTX 1080 appear better, is a serious disservice to the players of the game who happen to own hardware capable of producing major performance boosts from Async compute. In order to not appeaer like such a failure in DX12, Nvidia was willing to ruin the experiences of a large swath of players to achieve such misleading results. So even though it may appear like a redeeming result for nvida, in reality the RotTR numbers only further highlight Pascal's lack of async compute, for if the geme developers left the feature in like the originally intended, the GTX 1080's results would be much in the vein of the other DX12 games.To conclude, I do not see the GTX 1080 to be the "savior from heaven" that so many reviewers and fanboys hyped it up to be. Sure, the DX11 performance can result in advantages of up to 20FPS fpr the GTX 1080 over the Titan X, but considering DX11 is on it's way out and more and more titles in the past few months as well as in the months to come will be DX12, I feel as though the DX11 performance is not enough on it's own to warrant upgrading for current owners of a Maxwell/900 series GPU and especially owners of a 980Ti or Titan X. I think I can speak for many of us when I say that the community expected this card, especially considering the node shrink and new architecture, should be capable of a minimum of 60fps @ 4K and especially in DX12, but it just doesn't deliver. The problem is only excacerbated by the fact that since DX12 is "closer to the metal" than previous APIs and doesnt depend on driver support nearly as much, if the GTX 1080 isn't performing in DX12 now, it's not going to magically achieve a market leap in performance later though software wizardry as was capable with DX11. My advice is to avoid upgrading right now, unless youre coming from the 700 series or less, as the GTX 1080 just does not deliver what its price and technology would suggest. Personally, I'm waiting for AMD's Vega Architecture (the successor to Fiji/Fury X) as it will have HBM2 and will most certainly impress with its DX12 performance as all AMD cards have done so far.**I'd just like to iterate the fact that I am NOT an AMD fanboy, I have no alliegence to any brand, and only judge a given product on it's own merits, aka its price:performance ratio. My critical review of the GTX 1080 is solely motivated by my belief in the fact that DX12 performance is a factor of tantamount importance to any other, and the GTX 1080 just does not deliver in this respect.