Even if you meet or exceed the recommended PC specs for Deus Ex: Mankind Divided, you may still struggle run it on max settings, and that's by design.
Prior to the launch of Deus Ex: Mankind Divided, developer Eidos Montreal revealed the game's minimum and recommended PC specs.
This is standard precedence for any respectable studio. Unfortunately - and Mankind Divided is only the latest victim of this - we never know what graphical quality developers have intended for each set. Does recommend mean I can max out everything at 1080p? And if I can, is the studio targeting 60 or 30fps for that spec?
All of these questions are never answered before release, and it's up to you to scour the forums on launch day to see what you can really get out of your PC setup.
For Mankind Divided, the PC performance thread on NeoGAF, and similar posts on Reddit and the Steam forums, are full of players running high-end hardware that expected to go in, set everything to max, and get a high frame-rate.
After struggling to maintain 60fps, many were left thinking the port wasn't up to snuff, since their hardware setups have clearly fared better with many other games. In response, developer Eidos Montreal penned a long forum post about exactly the type of performance the minimum and recommended settings are designed to deliver.
For minimum specs, Eidos is aiming to deliver 30fps at 720p, at the Low quality preset. Surprisingly, the game's recommended specs are designed for 1080p resolutions and 60fps on average, on the High quality. According to the post, Very High and Ultra presets are aimed at players "well above recommended spec" or those who don't mind running the game at a frame-rates lower than 60.
In fact, outside of a temporal AA solution, the only hard AA option the game offers (MSAA) is designed for those running SLI or CrossFire. This option, along with Contact Hardening Shadows, will make even PCs with recommended specs suffer.
The rest of the post goes into slightly more detail about each available graphic option, whether they're CPU or GPU intensive, and what type of PCs can handle them. Reading through user impressions, it seems getting a near-constant 60fps will be a challenge, even at 1080p.
DirectX 12 support is coming and things could improve, but AMD cards will probably see the biggest boost. If you're still experimenting with graphic settings, the update is well worth a read. For now, just don't bother with MSAA or CHS if you're targeting 60fps on anything but a Titan X.