- Set the mouse acceleration slider to one bar left of center.
- Set the Sensitivity slider to the lowest possible option.
- Make sure that your startup script (for example, xinitrc or xsession) contains the line xset m 0/0 0.
- Restart the computer.
- Perform a mouse and PS/2 or USB re-sync.
Make sure that the screen resolution (even in text mode) is at least 1024 x 768. Resolutions that are less than that can cause the mouse to not sync, no matter what is done. In Linux text-mode, setting kernel flags in your boot loader (for example, GRUB) will help to set this.