Moving this discussion to the Photoshop General Discussion forum. THicksbville please make sure you meet or exceed all of the system requirements for Photoshop CS6 Extended listed at http://www.adobe.com/products/photoshopextended/tech-specs.html.
3D tools are only available in CS6 Extended but according to the Adobe website there is no upgrade path from CS6 to CS6 Extended.
If that's truly the case then you'd have to subscribe to Photoshop CS6 Extended (either Single App subcription or Full Cloud Membership).
In addition 3D tools do not work on Windows XP and your computer must have a minimum of 512MB vRAM (that's different to normal computer RAM).