Horizon Zero Dawn's PC port releases on PC today and it's a great game that's now available to a wider array of players than ever before. But it has some serious problems, many of them technical in nature. Along with some unexpected bugs and some more expected problems from a console to PC port, Horizon Zero Dawn doesn't look as good as it should and it's doing some weird things with its graphics to get to the state it's in.
Digital Foundry performed an in-depth breakdown of the game and its pros and cons, but on a technical level, it's behaving very strangely. Right off the bat the reviewer found that even when set to 4K, the game was downscaling to 1080p, and then upscaling to 4K, resulting in blurry visuals and a massive and unnecessary performance overhead.
Fullscreen seems to automatically enable triple layer VSYNC, though one workaround is to enable borderless windowed mode, then back to fullscreen again... every time you start the game.
Still, that's a bug, something we can expect to be fixed. DF also found that some of the game's highest settings don't do much to really improve the game's visuals, especially shadows, where there's very little difference between even medium and ultra settings. There are some really wonky frame time issues which seem to appear out of nowhere, removing some of the fluidity of the game, causing stuttering, no matter what GPU you're running.
Weirder still, PCIExpress bandwidth was a major bottleneck for the game, thanks to the developer of this port using the PS4 style of sharing system memory.
If you run into weird issues with this game, use as many PCIE lanes as you can.
Horizon Zero Dawn needs a lot more work before it can be recommended in this state.
