Just as a public service announcement to the community - there's a guy who's liquidating a pile of matched Xeon pairs on eBay. His prices seem competitive, although not very many that will work with 1,1 Mac Pros, lots of the 55xx series, though.
http://shop.ebay.com/forty6_two/m.html?_nkw=&_armrs=1&_from=&_ipg=
I'm in no way affiliated with that guy, just passing the info on.
http://shop.ebay.com/forty6_two/m.html?_nkw=&_armrs=1&_from=&_ipg=
I'm in no way affiliated with that guy, just passing the info on.