Laptop Processor Vs. Desktop Processor

For a while now I've had a question which I hoped some of you all may be able to answer for me! Sager/Clevo notebooks have been known for using some very powerful desktop processors in their notebooks instead of just the standard laptop line of processors. For instance, while several Clevo notebooks used the Turion 64 X2, the Clevo D900K used the socket 939 Athlon 64 X2 and Athlon FX line of desktop processors.

So my question is, is there really a noticable difference between the laptop processor and desktop processor when used in a notebook? I mean, there obviously would be a little more heat issues (personal experience with my D900k) but processing raw power-wise, is there that much of a difference?

I'm more of an AMD person, so most of my comparison and understanding is in these lines of processors. However, I'm curious if the Intel Core Duo and Core 2 Duo lines would have differences as well between desktop and laptop processor lines. This is actually a pretty big decision factor for my friend in a possible new Clevo notebook, and for myself even more for a future notebook a few years down the line.

 

Well, in the previous generation, the majority of mobile processors didn't offer the higher end power, that desktop processors had. So, they were implement into notebooks, at the expense of battery life. However, now mobile processor have become very powerful, and theres little point in putting a desktop processor into a notebook. The Merom core, which Core 2 Duo is based, is very similar to the Conroe core, and that is a desktop processor.