Canon 1D4 Noise

I am not sure if I am doing something wrong, but there seems to be an awful lot of noise in my pictures when using the 1D4 at ISO 400 and above. I don't remember seeing this much noise in the 1D3.

This is using 1D4, 24-70 2.8L, ISO 400, f4, shutter speed 1/160. Processed in Aperture 3.0.2 with no adjustments.

Any ideas/comments would be most welcome