Newegg has the s939 Opteron 175 for $141 less $25 instant discount and free shipping. That's $116 shipped!
AMD Opteron 175 Denmark 2.2GHz 2 x 1MB L2 Cache Socket 939 Dual Core Processor - Retail
$25 off promo code: EMC1009CPU03
AMD Opteron 175 Denmark 2.2GHz 2 x 1MB L2 Cache Socket 939 Dual Core Processor - Retail
$25 off promo code: EMC1009CPU03