Currently using PS CS6 64-bit on a new PC. Never had problems with PS in my 5-6 years until today....
When I open an image (tried both.jpeg, .png) the window/tab that opens confines the image to a fraction of the window space, leaving the rest of the window showing the background. I try to do full screen, I try to zoom in, I try to fit screen, and the image displayed will change buy will only stay in that one corner. I've changed the interface preference from tab to floating window with no avail. I've also tried moving the image window around and still same problem. The image is decently size, so it's not the image resolution.
For your reference, I've screenshot an image of PS with a 3600X1500 image opened to fit screen. That is where the image screen stays. Please help. 
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