Tech Report's very useful CPU decoder ring has received a much-needed update. As ever, the decoder ring will help you crack the increasingly complex code of microprocessor model numbers, allowing you once and for all to see clearly the difference between, say, a Pentium 4 570J and a Pentium 4 571, or an Athlon 64 3800+ and an Athlon 64 X2 3800+. It's all in there: Click to sort by code name, fab process, socket type, or recommended voltage. Scan to see whether support for the NX bit or 64-bit computing is present. Strain to figure out why the heck Intel and AMD decided to make so many variants of their products. Revel in the raw obscurity of the Turion model numbering scheme.

New in this hefty update is a column delineating the number of CPU cores onboard each processor, so you can navigate the multi-core madness with confidence. All of the new dual-core processors from AMD and Intel are now present, as are AMD's Turion mobile chips, the low-power Opteron HE lineup, and Pentium M models up to 780. If you somehow have failed in your geekly duty to memorize every model of processor so you know 'em stone cold, the decoder ring has you covered.