I solved my problem (could not play Half life or any other modes of the game in another way than “Sofware-mod” !! so i had no opengl nor direct3d)
my drivers were are all up to date (leadtek gforce4 mx440 running on wind2k) i downloaded this :
nVidia Refresh Rate Fix MKII for Detonator 40.41
(nividia’s script modified by a programmer)
at this addresse : http://www.voodoofiles.com/7780
and reduced my screen rate from 85hz to 75hz
now half life runs smooth and fine
Features of this file
Solves 60 Hz bug for DirectDraw, Direct3D and OpenGL
Lets you specify refresh rates from 60 up to 240.
Compatible to Detonator 40.41
Also works with older Detonators, since 28.32
Description
If you have a nVidia graphics card, you’ll probably know about the very common bug, that occurs together with the nVidia Detonator drivers under Windows NT/2000/XP: Normally, you can’t get a higher refresh rate than 60 Hz in the OpenGL/Direct3D modes, which makes you very blind after a while of gaming. I programmed this tool, to fix this bug, since I could not find an existing tool for this on the internet, which is compatible with the new official Detonator v28.32 drivers. There already were some tools around that supported the older Detonator versions.