Dual-Core CPU Buyer's GuideDual-Core CPU Buyer's Guide

AMD Athlon 64 3800+, 3500+, 3200+: Note that these models aren't Athlon 64 X2s -- "X2" denotes dual-core. These are plain-old single-core Athlon 64 designs, which were among the first desktop processors to implement AMD's groundbreaking 64-bit architecture.

The single-core Athlon 64s make a bit more sense price-wise than some of their Pentium 4 6XX competition. Perhaps that's because the scrappy semiconductor competitor fields fewer processors overall than Intel. A 2.0-GHz Athlon 64 3200+ lists for only $81. The top-of-the-line 2.4-GHz 3800+ sells for $120.

Low-End Single-Cores

Intel Celeron D 356, 355, 352, 351, 350, 346, 345, 341, 340, 331, 326: Here's a nomenclature no-no to remember: The "D" after "Celeron" does not put these parts in the same class as the Pentium D. These Celerons are low-end, single-core processors -- not dual-core devices. Note also that this family is divided up between Intel's Socket 775 and its rather aged Intel 478 socket. If you have the right motherboard, it doesn't much matter which one you get, since both types use a rather slow 533-MHz front-side bus.

The Celeron D 340, 345, and 350 use the 478 socket. The three CPUs also don't support Intel's 64-bit EM64T instruction set extensions. The Celeron D 326, 331, 341, 346, 351, 352, 355, and 356 are all socket 775 and do support EM64T.

If you're insistent on going single-core, and if your computing needs really are limited to everyday tasks, probably nothing fits the bill better than this family. Along with the aforementioned 2.53-GHz Celeron D 326 going for a scant $31, you can get a 2.93-GHz 340 for $40 or a 3.2-Ghz 350 for around $50. My suggestion, though, is to stick with the two most modern members of the family: the 3.2-GHz 352 and 3.33-GHz 356. Those two are the only Celeron Ds that have the added advantage of being 65-nm parts; the others use the older 90-nm process. They can be purchased for $69 and $74, respectively.

AMD Sempron 3600+, 3500+, 3400+, 3200+, 3000+: What is it with low-end processor names? "Celeron" sounds too close to "celery" for my taste. And "Sempron," which seems to have been chosen to connote the Marine slogan semper fi (always faithful), instead makes me think "simp," for simple. Which, like their Celeron competitors, they essentially are.

Like the Celerons, the Semprons come in versions spread among two different sockets: AMD's older 754 or its new, DDR2-supporting AM2. The Semprons also boast a faster system bus and use less power than the Celerons; however, most of the Semprons cost slightly more. The least expensive is the 3000+ at $61. (That chip runs at 1.8 GHz in its Socket 754 version, 1.6 GHz in AM2.) The family tops out with the $110, 2.0-GHz Sempron 3600+.