Does DirectX 8.1 work well with gmod?

Hello, I want to buy Gmod for my girlfriend, but her computer (ati x1100…) needs to use DirectX 8.1 for the source engine to work well (Half life 2 lags for her with DX9, works fine with DX8.1)

Does DX 8.1 work well with gmod? Because some games, for example Synergy, give problems when using DX 8.1

DX8 works fine with GMod, the game looks rather dim and murky with DX8, but works relatively fine. it will disable all bumpmaps and other shaders when using it in DX8, and most postprocessing filters will not work, but you will be able to have your usual GMod experience in DX8.

i use DX8 in all source games because my GPU hates phong shading, and i’ve had no real problems so far. there are some minor kinks (such as certain models looking bad without bumpmaps/shaders) but the game is still very, very playable.

two console commands you might want to use to get a ginormous performance increase on DX8 are:

mat_viewportupscale 1
mat_viewportscale 0.7

these will make distant 3D details rather blurry, but personally they allow me to use the “very high” texture setting with a constant 30fps on gm_bigcity. to revert this just type mat_viewportscale 1.

the GUI will NOT be blurry/small with this command (as running on a smaller res would), as it only upscales 3d aspects.

Fine, thanks! :smiley:
By the way, is there any way for using DX 8.1 appart from -dxlevel 81? Because -dxlevel 81 will reset all graphics settings everytime the game is launched.

unfortunately not. however i think if you remove that from launchoptions after starting it once GMod remembers your settings (at least it does for me)

Yeah, I used to use DX8.1 for my Gmod and the only major change I noticed was poor lighting. I got a huge FPS increase from it.

There is this command which does the same thing : mat_dxlevel 81

Here’s a launch option for ya, +mat_dxlevel 81! Makes the game force DX8 at startup, doesn’t reset any of the details in the video options

Thanks everyone!