Pentium III 1266S vs Athlon XP 2100+
Aggregate performance score
Pentium III 1266S outperforms Athlon XP 2100+ by a considerable 46% based on our aggregate benchmark results.
Primary details
Comparing Athlon XP 2100+ and Pentium III 1266S processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 3342 | 3242 |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Desktop processor |
| Power efficiency | 0.17 | 0.60 |
| Architecture codename | Thoroughbred (2001−2002) | Tualatin (2000−2002) |
| Release date | January 2001 (23 years ago) | July 2001 (23 years ago) |
Detailed specifications
Athlon XP 2100+ and Pentium III 1266S basic parameters such as number of cores, number of threads, base frequency and turbo boost clock, lithography, cache size and multiplier lock state. These parameters indirectly say of CPU speed, though for more precise assessment you have to consider their test results.
| Physical cores | 1 (Single-Core) | 1 (Single-Core) |
| Threads | 1 | 1 |
| Boost clock speed | 1.73 GHz | 1.27 GHz |
| L1 cache | 128 KB | 8 KB |
| L2 cache | 256 KB | 512 KB |
| L3 cache | 0 KB | 0 KB |
| Chip lithography | 180 nm | 130 nm |
| Die size | 150 mm2 | 80 mm2 |
| Maximum case temperature (TCase) | no data | 69 °C |
| Number of transistors | 37 million | 44 million |
| 64 bit support | - | - |
| Windows 11 compatibility | - | - |
Compatibility
Information on Athlon XP 2100+ and Pentium III 1266S compatibility with other computer components: motherboard (look for socket type), power supply unit (look for power consumption) etc. Useful when planning a future computer configuration or upgrading an existing one. Note that power consumption of some processors can well exceed their nominal TDP, even without overclocking. Some can even double their declared thermals given that the motherboard allows to tune the CPU power parameters.
| Number of CPUs in a configuration | 1 | 1 |
| Socket | A | 370 |
| Power consumption (TDP) | 72 Watt | 30 Watt |
Synthetic benchmark performance
Various benchmark results of the processors in comparison. Overall score is measured in points in 0-100 range, higher is better.
Combined synthetic benchmark score
This is our combined benchmark performance rating. We are regularly improving our combining algorithms, but if you find some perceived inconsistencies, feel free to speak up in comments section, we usually fix problems quickly.
Passmark
Passmark CPU Mark is a widespread benchmark, consisting of 8 different types of workload, including integer and floating point math, extended instructions, compression, encryption and physics calculation. There is also one separate single-threaded scenario measuring single-core performance.
Pros & cons summary
| Performance score | 0.13 | 0.19 |
| Chip lithography | 180 nm | 130 nm |
| Power consumption (TDP) | 72 Watt | 30 Watt |
Pentium III 1266S has a 46.2% higher aggregate performance score, a 38.5% more advanced lithography process, and 140% lower power consumption.
The Pentium III 1266S is our recommended choice as it beats the Athlon XP 2100+ in performance tests.
Should you still have questions on choice between Athlon XP 2100+ and Pentium III 1266S, ask them in Comments section, and we shall answer.
Similar processor comparisons
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