Q: Freezing Screen with strange graphic bugs > blackout computer crash & restarts

Hi All,

I'm a videographer and editor and work with some high-ress video files and my iMac often falls out during work or if I'm running Adobe premiere and Photoshop at the same time. My iMac should handle it but it won't. It freezes and gives strange graphic colors and blocks on the screen. (see photo's)

Anyone knows how to fix this?