Can anyone elaborate on why X5482 costs less than its desktop version where i7 desktops cost a lot less than Gainestown?
As far as I've read, desktop vs workstation chips don't differ much in performance. Sometimes none at all.
Ok there is no real difference in performance, you are correct. The QX9770 is supposedly more optimized for game type applications, but whether that translates in to real world performance has never been shown I dont think.
The price differences are because they are aimed at very different markets. The QX9770 is targeted at gamers and enthusiasts who will overclock it, this means the QX9770 chips may be of a better quality than those going in to the Xeons. The Xeons are for servers and workstations and as most customers will be buying two anyway Intel can offer it at a lower price. Think of it more as $1,400 for 4 cores and $2500 for 8.
For Nehalem the i7 parts are inline with Intel's previous high end desktop prices, $999 being the top spot. Intel will probably come out with a 3.33GHz, 3.46GHz or 3.6GHz processor with a $1400 price tag when they have built up enough inventory. The Xeons are more expensive because they offer more to the buyer over Penryn. Intel obviously feel they can charge that amount, again different markets so you can't compare the fact that desktop processors stayed similar but dual processors went up.