I got two of these CPUs to build a computer around an expensive 64-bit PCI card for a professor's lab. I could only find older Xeon boards that had a 64-bit PCI slot in anything less than a 4-socket motherboard, so I got a Supermicro X6-DVL-EG2 dual socket 604 board with a 64-bit PCI card slot as it was the most modern board that I could find. These were reasonably priced for Xeons, but they don't stray far from their Prescott roots as they generate heat in large quantities. The massive 1120g solid copper heatsink that Intel provides does a good job of dissipating heat, but dissipating 240W from an ATX case is a tall order and requires a lot of fan power to accomplish.

Two Xeons with HyperThreading show up as 4 CPUs to a Linux kernel and performance is decent- roughly that of a Pentium D 920- but they generate not quite twice as much heat as the 920 and cost more than twice as much, and a dual-604 board is much more expensive than a single-socket LGA775 board.

These are not weak or bad CPUs by any means, but there are much better choices out there if you can use them.