He has a laptop he already bought so what you are saying isn't possible. And he's not going to find any common laptop with 3ghz. Amd does not run smoother. In fact intel beats AMD in all areas.
Sony, Dell & HP all have laptops at 3.0Ghz for cheaper than what he paid for... but I understand that you're rocking a Toshiba so I can see how it would confuse you.
Secondly, Intel may be a pioneer in new core fields, but that doesn't make them the best. AMD usually waits until Intel has released something, reverse engineers it, works out the bugs that Intel suffers and releases most commonly a better quality product for cheaper. Intel has always had issues with working changes between 32bit software being used on 64bit hardware, but that's because it's designed to work better in an environment where everything is completely copasetic. AMD however excels much more in the opposite situations, so if you're playing a 64bit game on a 32bit system, it has better response time and easier access, again vice versa as well.
To answer the question though, the biggest area you're going to be suffering is with the 4gb of ram, while it may be sufficient to run the game, most laptop computers don't feature graphic cards with on-board memory, which means that in addition to the hundreds of patches & effects that this game is simultaneously trying to render, it's also buffing all the graphical displays through the same memory capacity, which means that you will be suffering significant lag despite if you do something like:
turn off the water effects and bloom. Turn down the sky effects too. You'll never notice that anyway. And maybe view distance to half. Everything else all the way up.
While it may cause you to squeeze out a few more FPS, it's still gonna be a headache.