Over the past few weeks I've encountered a problem with Photoshop CS 5.1. Anytime I make an addition or alteration to an image (not a photo, but a digital composition) whatever I've done does not appear until I zoom in or out of the image. I have also tried waiting a few seconds to see if the program just lagged but it still doesn't appear until I zoom in or out. An example would be if I add text to a document, while I'm typing the cursor will move as I type but the text doesn't appear until I zoom. This is with solid text and of a color differing from the background.
I've tried increasing the memory available to the program (I have given it about 6gb), still occurs. I uninstalled and re-installed the program, problem persists.
I'm running Windows 7 64bit, Intel i7 1.6ghz, 8gb ram, NVIDIA GeForce GT 320M w/1gb memory.
Any possible solutions would be very helpful. I've resorted to using CS2 and I would love to move back to CS5.