While its great that Square Enix has frequently patched Deus Ex Human Revolution on the PC, it’s unfortunate that mouse lag still plagues many players, even using the latest Build 1.2.633. Here is an easy fix to lessen the mouse lag.
Mouse Lag From Vsync
Assuming your settings are not beyond the capability of your graphics card, your mouse lag in DXHR is being caused by the Vsync setting in the options menu being turned on.
Others have speculated that SSAO (screen space ambient occlusion- a shadow option) causes it as well. While I can indeed verify that SSAO high vs. off does indeed make the problem worse, the SSAO setting doesn’t matter once you deal the vertical sync issue.
The Quick Fix
Seems I have done a lot of Vsync articles for various PC games lately. The fix here is the same 2 steps. Simply turn off the game’s Vsync and force it on in your graphics card control panel.
If you’ve never done this before:
- Open your graphics card control panel’s 3D Settings
- Find the Deus Ex game profile in the list
- For Nvidia- set Vsync option to Force On
- For ATI- set vertical refresh to Always On
- Turn off Vsync in the game’s options menu
Next time you launch your game, you should notice the mouse responds much better than with the in-game vsync and everything else remains the same. This will not eliminate the lag completely, but makes the game much more playable. Have fun!