Unless his schoolwork includes a lot of Photoshop, video editing or seriously heavy-duty mathematics programs he should stick with the dual-core. More bang for the buck right now for a simple Word/gaming machine, IMO.
You should also let him know that Gateway uses seriously low-end components and that he should expect to be spending time with tech support or even sending it in for "repairs." (read: replacement of the low-end parts that have given up the ghost)
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