AMD Athlon XP 2600+ processor used to be a “Khalif For An Hour” last August when it was released days before the Pentium 4 2.80GHz made it appearance. The first incarnation of this processor utilized Thoroughbred core with 256KB of L2 cache and 266MHz EV-6 FSB, but in Fall AMD decided to lower the core-speed, but increase the bus speed to 333MHz. Looks like the Athlon XP 2600+ CPU will undergo another change: later this year AMD will launch a microprocessor with 512KB of L2 cache and 2600+ model number.

Readers of X-bit labs already know that AMD will gradually phase out its processors with Thoroughbred core by substituting them by CPUs with 512KB of L2 powered by Barton core in higher-end market segments. There will be also lower-end CPUs on Thorton core with 256KB of L2. Basically, Thorton is the same Barton, but with half of L2; it will act instead of the Thoroughbred when the latter is gone.

As a result of AMD’s rejigging its product lines, the company will add another processor with 512KB of L2 cache in its family. This will be the already mentioned Athlon XP 2600+ chip now boasting with 333MHz EV-6 FSB and 512KB of L2 cache. It will also work at lower clock-speed compared to other chips with the same model number: 1917MHz. As a result, you will be able to find three totally different microprocessors on the market branded as Athlon XP 2600+:

• Athlon XP 2600+: Thoroughbred, 256KB L2, 2133MHz, 266MHz FSB;
• Athlon XP 2600+: Thoroughbred/Thorton, 256KB L2, 2083MHz, 333MHz FSB;
• Athlon XP 2600+: Barton, 512KB L2, 1917MHz, 333MHz FSB.

Needless to say that these chips have different performance depending on application, so, you will have to choose carefully which one is better for your needs.

Note that in the end AMD will have CPUs utilizing Barton cores only, hence, all “Thoroughbred” chips will be gone at some point. As a result, the Sunnyvale-based chipmaker will offer the following processors with 512KB of L2 cache:

• Athlon XP 3200+: Barton, 512KB L2, 2200MHz, 400MHz FSB.
• Athlon XP 3000+: Barton, 512KB L2, 2167MHz, 333MHz FSB.
• Athlon XP 3000+: Barton, 512KB L2, 2100MHz, 400MHz FSB.
• Athlon XP 2800+: Barton, 512KB L2, 2083MHz, 333MHz FSB.
• Athlon XP 2600+: Barton, 512KB L2, 1917MHz, 333MHz FSB.
• Athlon XP 2500+: Barton, 512KB L2, 1833MHz, 333MHz FSB.

Lower end and mainstream chips, such as Athlon XP 2400+, 2200+, 2100+ and 2000+ will provide the same technical specifications as now: 266MHz FSB and 256KB of L2 cache. The only difference will lie in the core, instead of good-old Thoroughbred, the newer Thorton will be used.

I believe that changes in AMD product line mentioned herein will start to take effect sometimes this Summer, so, keep your eyes open.