Let me list the insults:
1) "Tell him to either (i) go and discuss his needs with someone at a good computer store that supplies both sorts of machines, or (ii) buy the one that looks flashiest, costs most, and will increase his percieved status appropriately." ii assumes that he is the kind of person who would do that. He is not, although he is well off -- with no need to show that he is.
2) "It's clear that you don't know the answer, so how can you possibly advise someone else? By listening to a bunch of people that you don't know, all with their own agenda? I don't think so. Do yourself and your friend a favour; don't offer him advice on things that you don't know about." That is replete with unfounded assumptions. Actually, I had my own idea of what to tell him -- very similar to OtheHill's answer -- but wanted to get some other information, ideas, opinions, whatever.