At $139, the FX-55 is in an interesting spot: it's out of the scope of AMD's Athlon 64 X2s and Intel's Core 2 Duo dual-core processors, and thanks to its 2.6GHz clock speed and 1MB of cache, it's is also a good deal faster than other sub-$150 single-core processors. Add the FX line's unlocked multiplier and a fairly overclocking-friendly 90nm San Diego core, and the FX-55 starts to look like a sweet deal.
Of course, this chip will only fit into Socket 939 motherboards, so users looking to build a Socket AM2 system with DDR2 memory need not apply. However, we think the FX-55 could be an interesting choice for owners of current Socket 939 systems who'd like to crank up their system's single-threaded performance without breaking the bank. Props to forum gerbil Dposcorp for finding this deal.