Originally Posted by cdawall
either way isn't it lower than the competing C2Q based xeon?
Not really. Looks like the Xeon is rated lower, only by 10w, and that's on 65nm. Although comparing the chips themselves does you no good. You have to compare the entire platform, and the mch is on-chip in the Opterons, but not the C2Q Xeons. They'd probably come out roughly equal. I think the 45nm C2Qs might pull ahead tho.
Now, you can directly compare Nehalem and Phenom chips in terms of power draw, as they both have the mch on die, and nehalem comes out ahead there, at 80w in this clock/performance range.