As discussed, AMD/ATI graphics cards using the Catalyst driver can cause problems related to OpenGL. For example, in LR4 edititng a file in CS6 results in Photoshop disabling the graphics GL accelleration and some plugins report a 126 error. I found that AMD's Catalyst 4.2 Beta Support Win7 Vista driver solved the issue.
Then AMD introduced the Catalyst Win8 Consumer Preview driver and the 126 error returned! I reverted to the Beta and all was well again.
Adobe Photoshop doesn't recognise the OpenGL acceleration on my ATI/AMD HD 5700 card unless this driver is installed.