My Mamba..
randomly ( 2 mins 30 mins 1 hour it would vary) any clickable object (start bar, folders, top edges of windows) would pixilate like the vid card was going bad.
tried different vid card drivers, tried several versions of the mamba drivers with no success.. after about three days of workign with it i returned the mouse for another brand..
i should mention that the pixilation issue rendered the machine pretty much inoperable requiring a reboot and system restore.. ( restore before the driver for the mouse was installed)