GD2 on another power source

[RafaelSpe]

Hi people!! Im in a strange problem....lol..

im drawing a screen in GD2 and when i use the usb cable, everything is fine... But when i put the 9v battery on arduino, the screen turns white and nothing appears..

I have another  strange behaviour on GD2 that only works when i press the reset button on the board...

any ideas guys?

Thanks for your time!!

RafaeSpessotto