Core 2 duo vs core 2 duo mobile

Obviously a desktop Core 2 Duo is more powerful than its laptop equivalent, which needs to consume less power so that battery lives remain decent.

In any case, which specific processors are you looking at?

It depends on the models you are comparing,new Core2Duo mobile CPUs have 1066MHZ FSB + 6MB cache which is pretty good and they are like the older desktop Core2Duo's which had 1066MHZ FSBs.

You can always build a more powerful desktop for less money than a laptop.

If it's simply a matter of raw processing power then decide on the budget and go from there. If you have a very limited budget maybe go AMD if you have a little more I'd go with the Intel Core i7 920, 6GB DDR3 1600MHz etc.

It also looks like Larrabee has a lot of potential to add to processing and that's going to require a desktop. Of course it's not out yet, but any really good program that requires extensive processing is going to support Larrabee, GPU (CUDA, STREAM?) or both.

If you aren't a gamer at all, hold off on an expensive video card unless your program uses the GPU (unlikely).

Your laptop is not going to very upgradeable. As well, the slower hard drives do make a noticeable difference. I don't know how demanding your requirements are but I really would recommend going with a desktop.