Yeah, this is a cable problem, for sure. I know it's hard to look at the cable, seeing nothing seemingly physically amiss with it, but still have it ghost this way, even at the lowest possible resolution you could try, but any misplaced pixel at only 640x480 means your cable is fuckered. I made this mistake myself thinking that the $15 cable was good enough. Microsoft's cable is much thicker, and it's either that or magic fairy dust that makes the difference, I really have no doubt that the official cable would cure all ills pronto. And that's just because I've been where you are now!