> "Jessie" is not generally very responsive compared to "Wheezy", display > update and mouse tracking is very very slow.
Could it be that your wheezy install did not use Gnome-3 and that you're now using the standard Gnome-3 desktop (which presumes existence of 3D GPU acceleration) on a system whose graphics card either has no 3D abilities (or whose 3D abilities are not supported by the X.org driver)? If so, try some other desktop: Gnome classic (not sure if it relies on 3D hardware as well, tho), Mate (a derivative of Gnome-2), xfce, ... Stefan