Stencil test order

Is it possible to change the operation order of the openGL pipeline?

In particluar I want to be able test the stencil buffer BEFORE anything else. If it fails I want opengl to go onto the next pixel without doing any texture or Z operations.

I really doubt this is possible, although I can’t promise. But anyway, why would you want to perform stencil and Z tests at different times? On todays hardware they are performed at the same time. So doing what you suggest would be slower. And the pixel is first tested against the Z/stencil before anything else, and therefore texturing won’t be applied if Z and/or stencil fails.