I have the MS Intellimouse PS/2 and I have this problem in X. The pointer keeps on move to the top left corner of the screen like something is pulling it there. I don't seem to have any control over it at all and am clueless on why this is happening. I did mouseconfig and chose MS Intellimouse PS/2 and I also did xf86config and chose the same thing for my mouse. Can anyone help plz? Thanks in Advance.