Your friend's best bet would be to look at an AMD.
How about this one?http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=7044324&Sku=B69-0278
Note, I HIGHLY recommend grabbing a better power supply, may put him over 415, but perhaps he can squeeze another 20 bucks.
Comes with 2 gb of ram, ddr2 admittedly, but gives a case, optical drive, 1.5 terabyte drive, Asus board, and Athlon II quad. For your budget, I don't know that you will do much better. Especially because this comes with Windows 7 OS bundled. So I would say grab that deal, put a better power supply in from the get go. Later on, put 2 more gb of ddr2 in for a total of 4 gb, then put a dedicated card in like a gts 450 or 460 and your friend should have a nice little gamer rig.