Hi,
Take a look at this document:
http://helpx.adobe.com/photoshop/kb/photoshop-cs6-gpu-faq.html
And here specifically:
Updated display drivers can fix many issues, such as crashing, incorrectly rendered objects, and performance problems. See Update the video display driver. Then, turn on Use Graphics Processor in Photoshop preferences.
To update the display driver on Windows 7 or Vista, use this TechNote.
(http://helpx.adobe.com/creative-suite/kb/update-graphics-driver-window s-7.html)
To update the display driver on Windows XP, use this TechNote.
regards,
steve
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