Any reasons for the G258 if you don't plan to overclock? I would look into the Athlon X4 860K if I were you (it has 4 cores vs. the G258's 2 cores and is clocked faster at 3.7 GHz). Here's a build with the X4 860k that is within your friend's budget. The case I picked out is a CM N200 that is marginally more expensive than the Core 1000 but offers some room for cable management.
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