25R8908 - IBM 2.80GHz 800MHz FSB 2MB L2 Cache Intel Xeon Processor for eServer xSeries 336

As you know, the Xeon Foster is called "Willamette with SMP support", and the Xeon Prestonia is known as "Northwood with SMP support". These CPUs are based on the same core. Besides, the pairs of "Foster - Willamette" and "Prestonia - Northwood" are based on the same fabrication process and have the same L2 cache size. The processors have different sockets, but if you look at the signal assignment diagram the pins of the Socket 603 processor will show that most of them control either power supply or ground, i.e. they are not significant.