AMD Duron 1.2GHz Review
By Vince Freeman :
December 13, 2001
Physical Architecture
In a basic sense, the Duron 1.2 GHz shares architecture similar to the Duron 1 and 1.1 GHz processors. These are all based on the AMD Morgan core, which is also a derivative of the Athlon Palomino core found in the popular Athlon XP. One important note to make is that both the Morgan and Palomino cores are basically enhanced versions of previous Duron and Athlon designs, and share the same 0.18-micron process. We'll have to wait until the Appaloosa and Thoroughbred before we see what AMD has up their 0.13-micron sleeves.
The Duron 1.2 GHz separates itself from the higher-end Athlon and Athlon XP through its 128KB L1/64KB L2 cache design. In addition to the lower core speed, this cache design also helps position the Duron as the entry-level option in the AMD processor line-up. Since the Athlon XP has made the full transition to the 266 MHz front-side bus, this leaves the newer Duron models as the only current AMD processor that still makes use of the 200 MHz bus speed. In fact, there are no Duron processors that can use a 266 MHz bus as the default speed. This amounts to a potentially lower system bandwidth for the Duron compared to the Athlon XP.
One area in which the Duron does not differ with the Athlon XP is in regards to core voltage. In previous Mustang core models, the Duron featured a lower 1.6V requirement compared to the 1.75V of the Athlon. Now both AMD processors require 1.75V as the default, which is a bit surprising since many of the Morgan core enhancements related to lower core voltage and heat levels.
Morgan Core Enhancements
While much has remained the same with the Duron Morgan core, there have been a few notable enhancements. The fall into two basic areas: the addition of an improved Data Prefetch function and the improved 3DNow! Professional instruction set, which is now fully SSE-compatible.
Data Prefetch and 3DNow! Professional
Data prefetch essentially tries to predict the data that the processor will need and then loads it into the data cache. This type of performance enhancement can pay dividends with higher performance and it is a core element of the Pentium 4 design. This portion of the enhanced Morgan core is expected to contribute the most to any increased CPU performance, especially since it has a potential effect across all games and applications.
AMD has also added 52 new instructions to their SIMD set, and now calls it 3DNow! Professional. What this essentially does is make the new Duron models SSE-compatible and put them on equal footing with competitive Intel Celeron and Pentium III processors. Although most programs are not SSE-enhanced, games such as Quake 3 should run faster. When you boot the game with the Duron 1.1 GHz installed, it does display Pentium III Optimizations as being enabled.
