My card is Nvidia GeForce 6600 GT, I opened some properties dialog and I saw that there was a setting about Direct3d and OpenGL settings that was set to balanced (between quality and speed). I changed it to "Let the 3d app decide" and it seems to make a difference... I test it and have no problems now....

I will update the driver anyway, although I think the only difference will be some added products that are supported....

I hope I did it and that everything works OK now, it was very annoying...