I love these quarterly builds . . . even when I don't agree with certain choices, I learn something new each time. And the composite picture they draw gives me confidence tweaking my own builds to my own needs. Here's where I'd differ with your choices:
I think the Antec 900 is highly over-rated . . . I bought one for my first build based on internet buzz, paying $125 nearly 5 yers ago. It was needlessly noisy, dusty, heavy, and (IMO) ugly. It sits in my basement, unused. There are several quieter, cooler, positive-pressure dust-free cases out there to choose from.
I understand choosing a 120GB SSD when competing for a "value" crown. Personally, I prefer 256GB so I can comfortably keep all my current game interests stored there. But having chosen 120GB, I don't agree with the "green" choice for the main storage drive in a gaming rig, especially when you are so far under budget. I'd love to learn how gaming performance compares when using an SSD vs "black" vs "green". And how much power is actually saved by choosing "green".
Finally, I'd like to see your power efficiency measures put on the same basis as your other value measurement, ie, cost.
I was curious as to what the rather large power savings Q2 vs Q1 would actually save me. At one hour/day and $0.15 per KwH, the savings were $3.67 per year at Idle, $7.01 if cpu-bound, $4.16 if gpu-bound and $9.09 per year if CPU+GPU bound. So a 4-hour per day gamer, 1-hour per day browser would probably save ~$20 per year of use, or $81 over the 4-year life of the system.
I'd also like to know/verify the true power consumption of these systems in "sleep" mode. I find it ironic that many folks who want to go green also leave their rigs asleep 20+ hours per day. Assuming only 10W consumption by the entire system when in sleep mode, that costs $11 per year in wasted power.