We had a similar situation about a year ago and as I recall it had to do with a/c ground, try a three way adapter from the L/T to a/c and see what happens it is woth a shot.
Windows Vista 64
2.1GHz AMD Turion 64 X2
The problem is, the monitor works just fine, when is connected to my desktop through VG, but when I connect my laptop through VGA too, some flashing lines appears, especially when the background is gray. Is my laptop VGA port damaged? My monitor isn't correctly configured? Or something else?
Thanks in advance for the replies.