Screen Flickers on Raspberry Pi
Do you have your RaspPi connected to a VGA monitor using some kind of HDMI-VGA adapter? If so, there is a good chance you will experience this problem
This looks similar to the adapter I am using for the Raspi. I noticed that the picture on my monitor would disappear when I moved the mouse, and more often when the computer was under a load.
It turns out that the converter uses +5V from the HDMI port, and when then voltage goes below a certain point, the converter cannot operate, so produces a blank screen.
The solution is to buy a Powered HDMI to VGA converter, or to rip the unit apart and give it direct access to +5V... and the closest source for that is normally a USB port from a powered hub. By carefully soldering a USB cable to the converter (and disconnecting the 5V source from the RasPi), you can give the converter all the power it needs
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