Does anyone have any stats for what the lowest possible power consumption is for an i5 under full load? I've been toying with the idea of building a custom laptop out of desktop parts and I was hoping to use a picoPSU-120, but it seems like all the i5 reviews show that Sandy Bridge comes awfully close to 120W max or exceeds it (see, for example, http://www.hardwarecanucks.com/forum/ha ... ew-20.html
I don't need any fancy graphics, integrated will do just fine. i3 won't cut it because I need at least four cores for parallel compiling. Some reviews seem to indicate that Clarkdale is more power efficient than SB, but that seems strange. On the other hand, if Clarkdale really is lower, then I'd be OK with that. I know there are the S and T parts, but they seem much more expensive (especially 2500T) whereas I can get a i5 2400 for $150. Could I undervolt to get reliably around 100W under full load for hours? Do I need the 2500K for that, or will any i5 with the appropriate motherboard do? Also, n00b question: does undervolting "damage" a CPU the way overclocking does?
I'm open to AMD, if anyone knows of a way to get the wattage down (main rig is an X6 and I love it).
EDIT: Also, is there generally a difference in power consumption between mATX and mini-ITX boards if the CPU and GPU are the same? Can anyone recommend a "low power" motherboard, if such a thing exists?