Nikon D300 RAW images have alot of noise /...

Question

I retired my D200 and picked up a D300, to my surprise the RAW images are lousy. They have alot of noise, at ISO 400 uncompressed. I am using capture nx v. 1.3 latest version for processing. The JPG images are stunning, so my guess is that Capture NX is s******g up the images.

Mike