[Newbie]jumping mouse cursor (PS/2, xfree86 4.1.0-16

[newbie@XFree86.Org (Rudolf Divicin)]

Hello.

I have problem with mouse cursor.
When I move cursor through screen, it often unexpextedly and very 
quickly jumps to border or corner.
I have PS/2 mouse, linux 2.4.18, card with i740 chip, AMD K6/2 proc., 64MB 
RAM, gnome 1.4.
(on gpm mouse work correctly)
What may be demaged?

Rudolf Dovicin