Good points Bribera, but by going by that, most computers, if not, all computers, would not payback the energy released.
Then there's the carbon footprint for transport and the computers' ineviatble disposal. In my opinion it is better to reuse, and is part of the reason for buying unwanted processors and motherboards, and giving away computers on local initiatives for local people such as Freegle and Freecycle.
However the OP is doing the process from new parts - so is trying to be responsible in his computing choices.
Initially, all Atom motherboards on the consumer market featured the Intel 945G chipset, which uses 22 watts alone. As of early 2009, only a few manufacturers are offering lower power 945GSE-based motherboards to end users, paired with the Atom N270 or N280 CPU.
Which is why you see Atoms with tiny CPU heatsinks, and much bigger chipset heatsinks. Using TDP as a guide for power consumption isnt that bad an idea, but its go its issues-
TDP values between different manufacturers cannot be accurately compared.
22W for an integrated GPU? That surely isn't right. My laptop has an nvidia 8600M GS and the whole laptop uses about 40W at max load, 20W at minimum load. I can't see how the graphics card can use such a big proportion of the total power.
Its not just a graphics card, its also the memory and PCI-E interface and the connection to the southbridge.
Just for a laugh, see this pic-
The Atom CPU is under the little passive cooler at top. The active cooler is for the chipset LMAO.
The issue of graphics cards is something that will be turned on its head when ARM processors eventually hit the netbook world. The graphics is part of the processor and they use more like 1-2 watts (for now). Expect twenty four hour and beyond battery goodness.
While I fully intend on leaving as big of a carbon footprint as I possibly can, because the energy companies give me a paycheck. I did find the need to build a couple low power low cost systems ( a Server and Desktop.) I used the Intel D945GCLf2. I put 2 gigs memory and and 1 terra byte drives
I unit had a dvd burner the other just a reader. Both units with cases and PS cost $600us the 330 Atom id pretty fast at 1.6 Gig cause of the hyperthreading and duo Atom chip. the 20 inch 9/5 Samsung was $105.
It doesn't use much power and the board assy is leadfree. I will just have to figure out another way to do my part to warm up this freezing planet. but I do have a pretty nice green desktop server combination.
I liked this post.
I just had few questions.
Why only Ubuntu OS?
Is there any difference between Windows 7 and Ubuntu 10.04 for going green?
Does Ubuntu utilizes less power than Windows 7?