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Good try, but you forgot some pretty important details.

The iMac on the top of that chart is the maxed out 27" iMac with the 3.4GHz i7 processor upgrade. That's a $2200 machine with no other options, pre-tax. The base 21" iMac with a 2.5GHz i5 won't be near that. However, it also won't be near a $2200 price tag - it's a cool $1000 less. The base Mac Mini (which I still recommend to the OP) starts at $600. That's a much better initial investment than blowing over $2200 on a machine he's not even sure he'll like.

Find a chart comparing the base 21" iMac and the Mac Mini.

True, but he did say that he wanted to play games on it, and while I agree that the top of the range iMac may be more than he wants to spend, I think he will be disappointed with the Integrated Intel HD 3000 chipset in the base Mini, If he is going to go the Mini route then he should really consider the one with the 6630M Graphics chipset in it. The Mini with the 6630M will run games like Portal at around the Same FPS as the 21.5" 2.7Ghz iMac (around 70 FPS).
 
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