Since upgrading my secondary to VistaPremium SP1 when I move my mouse from my primaries desktop to the secondaries it won't turn the screen back on if it's been turned off for power saving reasons. The mouse cursor location does move past the edge of my primary and is presumably moving across the secondarys display. eg if I move the mouse 2 inches off the edge of my primary I have to move 2 inches back the other direction to recover the cursor on the primary.