Unable to enable DirectX 11 in Deus Ex: Human Revolution

I have purchased the game when the game actually launched. The game is really best in graphics as well as the gameplay is nice but having only one problem while playing the game. There is the option in the game which will allow us to enable the DirectX 11. But when I see this option this option is disabled in the game and showing as the red and I can’t able to change it to enable. So why this option is disabled in my game. So how can I enable it? Anyone having this issue with the game.
My system specification is
• Operating System: Windows 7 64bit service pack.
• Graphics card: ATI Radeon 4870 in crossfire mode having 2 cards

the problem is not with the game. The problem is actually is with the drivers of the graphics card. So I will suggest you to update the driver and try to remove the graphics card driver and install the latest drivers. And check the game it will enable the DirectX 11 option in the game.

I don’t think the problem is with the game. Check the minimum system requirement and the recommended game requirement

Minimum:
• Operating System: Windows XP, Windows Vista or Windows 7
• Processor: dual core 2 GHz
• RAM: 1 GB RAM / 2 GB
• Graphics card: NVIDIA GeForce 8000 series or ATI Radeon HD 2000
• DirectX: DirectX 9.0c

Recommended:
• Operating System: Windows 7
• Processor: AMD Phenom II X4 or Intel Core 2 Quad
• RAM: 2 GB
• Graphics card: AMD Radeon HD 5850
• DirectX: DirectX 9.0c

Check if it will meet the game requirement.

I think the graphics card you are using doesn’t have the support for the direct X 11 it will support maximum of the direct 10.1. I have checked it over the AMD website. So since your card is not supporting the direct 11 and not having the full support of DirectX 11. Even you have windows 7 you cannot able to enable the Direct X 11 in game. Since the game required the full DirectX 11 support.

I am also facing the problem with the game I am using the graphics card HD 6970. And the drivers are also updated for the card. But still I am getting the problem while playing the game I am not able to enable the Direct X 11 in game the option in my case is actually grayed out. So what will be the problem and why it is actually gyred out as what I know my graphics card has full support for the DirectX 11. Is this problem is due to the Game glitch itself. Or it is due to my system.

your problem will be resolved with the patch. The patch for the game is out now for download so download and apply the patch to the game. And then check that option in game settings.

The game looks great in the DirectX 10 and there is not that much difference in the DirectX 11 and 10. So I will suggest you to not to enable the setting. Since when I have tried to play the game in the direct X 11 it is giving the problem and game just gets freeze after some time. The system will be required which has the higher configuration to user the game in the DirectX 11 since the game is required more resources and the VRAM is also required higher to get game work perfectly.