The Intel Xeon MP 3.00 was a server/workstation processor with 1 core, launched in March 2005. It is part of the Xeon MP lineup, using the Potomac architecture with Socket 604. Xeon MP 3.00 has 4 MB of L3 cache and operates at 3 GHz. Intel is making the Xeon MP 3.00 on a 90 nm production node, the transistor count is unknown. The multiplier is locked on Xeon MP 3.00, which limits its overclocking potential.
With a TDP of 135 W, the Xeon MP 3.00 consumes a lot of power, so good cooling is definitely needed. ECC memory is supported, too, which is an important capability for mission-critical systems, to avoid data corruption. For communication with other components in the machine, Xeon MP 3.00 uses a PCI-Express N/A connection. This processor lacks integrated graphics, you might need a graphics card.
The SSE4 instruction set is not supported, which can cause problems with modern games, as they require that capability.