masterawr: Open the UT2004.ini file found in the system folder.
look for this code....
[Engine.Engine]
RenderDevice=D3DDrv.D3DRenderDevice
;RenderDevice=D3D9Drv.D3D9RenderDevice
;RenderDevice=Engine.NullRenderDevice
;RenderDevice=OpenGLDrv.OpenGLRenderDevice
;RenderDevice=PixoDrv.PixoRenderDevice
edit it to read
[Engine.Engine]
:RenderDevice=D3DDrv.D3DRenderDevice
;RenderDevice=D3D9Drv.D3D9RenderDevice
;RenderDevice=Engine.NullRenderDevice
RenderDevice=OpenGLDrv.OpenGLRenderDevice
;RenderDevice=PixoDrv.PixoRenderDevice
Basically you add a ; in front of the "RenderDevice=D3DDrv.D3DRenderDevice" line
And you remove the ; from the "RenderDevice=OpenGLDrv.OpenGLRenderDevice" line
I don't know why the guys at gog haven't set the game up this way as the default. You want to use openGl as the primary renderer for all old games since it is the most compatible video renderer and most old games look better vs direct 3d / direct x.
OpenGl has always been a superior to direct 3d, it makes your video card run less hot, it is more backwards compatible and it is more efficient. The reason why developers think direct 3d / direct x is better is because it has been forced and bribed by Microsoft.
Anyway I hope this solves your issue :)