Value
The Athlon XP 1900+ may be a high-end processor, but AMD is doing their best to keep the prices low. Current online prices range anywhere from $245-$250, which is significantly higher than the $190+ range of the Athlon XP 1800+, but still much lower than the $400 price tag of the Pentium 4-2.0 GHz. Price comparisons to the Pentium 4-1.9 GHz are more interesting, as AMD seems to be sticking to their strategy of undercutting the Pentium 4 of the same model/speed rating. The Athlon XP 1900+ is currently $20-$30 lower than the Pentium 4-1.9 GHz, which is great news when you realize the XP 1900+ can take the Pentium 4-2.0 to town. From an overall price-performance viewpoint, the Athlon 1800+ may be a slightly better value, but you still won't have to pay an Intel-like premium for the fastest AMD Athlon XP 1900+ processor.
In terms of platform value, going the Athlon XP/DDR route will save you money compared to a Pentium 4/RDRAM combo, though AMD seems to be betting heavily on the DDR horse. In the performance market, this is of little consequence, but when looking at more value-oriented systems like Pentium 4/i845 computers, AMD may have left a big opening for Intel.
If you build their own PCs or buy through a local dealer, the DDR choice has little impact, but large OEM vendors buy far more SDRAM than DDR and receive heavy quantity discounts. Since outside of the odd KT133A board revision that actually supports the Athlon XP, AMD doesn't really have a recommended Athlon XP/SDRAM value platform. Due to both the popularity of SDRAM with value buyers and its lower volume costs to large vendors like Compaq and Micron, going DDR-only could cause the Athlon XP to exist far above the value segment.
Certainly the Duron is meant to fit that role, but the incredible flexibility of the i850 and i845 chipsets allow the Pentium 4 to slip into just about any price range. While enthusiasts will scoff, for those who like a ton of CPU juice with their low-cost SDRAM memory, the Pentium 4/i845 looks to have the advantage.
Conclusion
To put it bluntly, the Athlon XP 1900+ is simply the fastest processor we've had the pleasure to test, and is certainly the highest performing desktop CPU currently available. There are a few issues relating to potential upgrade incompatibilities and multiplier locking, but this CPU is fast enough and the KT266A platform inexpensive enough, to let those negatives slide. With the right mix of components, the Athlon XP 1900+ is a gamer's dream come true, and combines exceptional performance with a price that won't break the bank.
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