LJA, that Opteron 156 is rare as Throughbred-B 2800+.
FYI, for those who don't get the reference. When Intel's Northwood-Bs and Cs were giving AMD's Throughbred line-up a lot of heat. AMD promise to deliver a 2700+ and 2800+ Throughbred-B chips, but only a couple hundreds units were made.
Likewise, the Opteron 156 was never officially launched and only a couple hundred units were ever made. AMD was busy shifting their focus from S939 to AM2.
The UT2004's server uses a K8T890 (PCIe version of K8T800P) which was known to have the infamous "cannot work with dual-core K8" problem. That some might have consider to be the death for VIA's chipset division.
LJA is forced to resort to single-core K8s and the most powerful verison for S939 was ether FX-57 or very rare Opteron 156.
Ivy Bridge i5-3570K@4.0Ghz, Gigabyte Z77X-UD3H, 2x4GiB of PC3-12800, Sapphire RX Vega 64, Corsair CX-600 and Fractal Refined R4 (W). Kentsfield Q6600@3Ghz, HD 4850 2x2GiB PC2-6400, Gigabyte EP45-DS4P, OCZ Modstream 700W, and PC-7B.