That 1700 pound price is VERY suspiciously low.  A single Clovertown Xeon all by itself is very expensive.  I'd expect that is an absolute minimum price, possibly with only a single processor installed with "room to upgrade" later.

Some apples-to-apples (heh) comparison between a large spread of Intel chips, the pair of top shelf Xeons don't really put in that great a showing:
http://www.gamepc.com/labs/view_content.asp?id=x5355&page=8 dual Xeon render benchmarks
http://www.gamepc.com/labs/view_content.asp?id=qx6700&page=7 single QX6700 (quad core Core 2 Extreme) render benchmarks, with similar benchmark specifications as far as I can tell, and an interesting quote:
"A single QX6700 will outperform most dual-processor, dual-core Opteron and Xeon workstations now as well."

Also be aware that you're limited by the number of threads the render engine is capable of operating in - since even Poser 7 is limited to four threads, having more than four cores won't benefit you in the slightest, although it would leave you with free processor to do other things with.  This will vary by application though.

My Freebies