mat_dxlevel

mat_dxlevel is a console variable available in all Source games except Left 4 Dead engine branch (or some third-party branches) and above.

Note:This command is not available in any game made using Left 4 Dead engine branch and later branches, or in some third-party branches.
Furthermore, since around Source 2007 up to Source 2013, only DirectX 8.0 and 8.1 levels are supported, DX7 and earlier was dropped (except in Portal with RTX).

mat_dxlevel changes the DirectX (feature level) mode used within a Source game. The player is only able to use modes that their hardware supports. The format is

mat_dxlevel [DirectX version]
mat_dxlevel 60 - only on Source 2004, 2006
mat_dxlevel 70 - only on Source 2004, 2006 (and Portal with RTX/RTX Remix games)
mat_dxlevel 80
mat_dxlevel 81 - Softer shadow
...

For DirectX 9 the value depends on the hardware's capability:

mat_dxlevel 90 - DX9 with Shader Model 2
mat_dxlevel 92 - Mac/Linux only, same as dxlevel 95
mat_dxlevel 95 - DX9 with Shader Model 3
mat_dxlevel 98 - Xbox 360 only, always enabled
mat_dxlevel 100 - Source Filmmaker and Dota 2 (pre-Reborn), always enabled, game will still runs on D3D9, however.

This can also be specified with Launch Options, use +mat_dxlevel [DirectX version] on the launch options of any Source game to do so. Alternatively, you can use -dxlevel [DirectX version], however this specifies a number of extra presets, including but not limited to:

• Resolution
• Windowed/Fullscreen status
• MSAA sample count (mat_antialias)
• Motion blur (mat_motion_blur_*)
• Shadow depth textures
• Gamma (mat_monitorgamma)

Note:This command does not change the Direct3D renderer to run on other versions. All Source games will always run on Direct3D 9 (or 11/12 in some third-party games), regardless which mat_dxlevel is specified.

Warning:Using -dxlevel launch parameter makes alt tabbing in and out of the game really slow, this will also resets all video configs. It's better to use +mat_dxlevel launch parameter instead, or to place mat_dxlevel command inside a config file.
Futhermore, -dxlevel should be only used a workaround to fix the issue that the game (especially all Source 2013 games except Team Fortress 2) defaults on DX8 mode which may happen on some modern hardware.

See also

• DirectX Versions