Jonathan got it right in an earlier post, and it looks so nice i didn't want to say anything negative.

Firstly i wouldn't touch the face of the CPU

You have three flaws in your design, it seems the wall thickness is to great the face touching the CPU should be in the order of 1mm or less

The flow of water should be controlled in a backwards and forwards motion in that it forms a single cavity from start to finish forcing the water to travel over all the surfaces

The size of the cavity should match the area of the pipe and within the cavity's should be fins for maximum heat transfer

For best heat transfer it should be made of copper

Air water etc will flow in the easiest route, in your design you can go from start to finish ports bypassing the edges allowing heat build up.

Phil