When I use the glPointSize function on a computer with a 3d card, the point’s size always stay the same… But when I use them with a normal graphic card, it works.

Can somebody help me to resolve my problem?

try glGetFloatv(GL_POINT_SIZE_RANGE …

try to use glEnable(GL_POINT_SMOOTH) or glDisable

It’s possible that the card you’re using don’t support a point size > 1, in which case you could try using Zed’s suggestion to check how big a point the card will render. It may also be that glPointSize on the 3D card you’re using is broken. If you update the drivers in the card, your problem might be fixed.

Out of curiosity what kind of 3D card are you using?