What OS version are you using?
Have you installed all the Photoshop CC updates?
Does your video card meet the minimum requirements for using 3D features in Photoshop?
What does Help -> System Info say about your video card?
my OS version 10.9.3. 3.06 intel core 2 duo.
Yes I've updated my Photoshop CC.
My Graphic card ATI Radeon HD 4670 256MB
Reckon this is the problem? But previously it was working fine before I've changed my OS to Maverick.