I have a SD board that did not work at first and then replaced the AVG chip and it was cool. Ran it for about 6 hours and then all of sudden the screen was all stretched! Turned it off and the screen is fine but then 5 seconds later it starts to like pull line by line to the left like a wind storm blowing it over. Put the AVG chip back in my other SD board and it's fine so what would cause this? Also this board did this in two different SD cabinets so I know it's not the monitor or wiring. 
