Cycles Subsurface shader: GPU compute and CPU compute give totally different results Blender 2.67
Windows 7
Geforce gtx460

Head model with subsurface scattering and one texture
Cpu render - fine, but slow.
gpu render - face comes out black! (it was working at first it changed for some reason)

any suggestions? why should this happen.

Here is an image of the problem
The SSS shader has not been implemented for GPU rendering yet. It will always render black.
Update: SSS now works on GPU, so they should look the same.

If you're looking for quick renders, SSS is not a good idea. If you can get away with a simple Diffuse BSDF shader with a bit of Translucent BSDF, that'd be great.