nVidia and XP Pro OpenGL problems

Hi.
I’ve got some problems with games using OpenGL.
I’ve got a lot of artefacts and tearing on textures in games like Serious Sam 1 & 2, MDK2, Half-Life,…
The problem seems to be only on nVidia chips ; I’ve try with a GeForce2 MX and with an ATI Radeon. With the MX, I’ve got the same problems but with the Radeon all seems ok.
Anyone can help me?

Thanks