problem with mesh

tricky bug I render a a mesh like this pMesh->DrawSubset(...); this work on allmost all the computer I know, except mine. on mine in fact he renders only the faces on the border of the windows or on the limit of the clipping plane. when I move the camera he move the faces and continue to draw only face who intersect with the border of the clipping plane I render some others objetcs with draw primitive and they draw perfectly ... if someone has an idea where it can come from...