Gigabyte Motherboards for the AM3: Most Cost-Effective?

Depends on whether you already have ddr2. Prices are creeping up again for memory. If you can find a 2x2gb ddr3 kit for around $60, then I would go for it. Haven't seen too many rebates on ddr2 lately.

The price spread between 2 and 3 has narrowed considerably in the past six month (though, as o1die said, they are inching up again - I read why in the WSJ, but it escapes me now - this:
http://www.newegg.com/Product/Prod [...] 6820231166
was $50 a couple weeks back), and more manufacturers seem to be getting better at the 3; six months ago, I'd have said, stick with the 2, but now, it boils down to what you're willing to pay - you will get your money's worth either way...