Dear Martin,
Newegg files dual CPU boards under "server": here are about 25 dual
socket 940 Opteron boards:
http://www.newegg.com/Product/Produ...0162&Subcategory=302&description=&srchInDesc=
Lots of Tyan and Supermicros, one Asus board:
http://www.newegg.com/Product/Product.asp?Item=N82E16813131059
Note: I have a Tyan S939 motherboard, it has been absolutely great....I
hear that Supermicro makes great motherboards, and, I have always had
great luck with Asus as well.
Dual core socket 940 Opteron CPUs:
http://www.newegg.com/Product/Produ...2820275&Subcategory=&description=&srchInDesc=
If you are not familiar with Newegg, their customer reviews are a pretty
good source of information--must consider the source--some people give
bad reviews when an AMD processor doesn't fit in an Intel motherboard,
but, most reviewers are pretty knowledgeable, and make good points.
HTH,
BC