Pentium III 1400S vs Pentium III 1266S
Aggregate performance score
Pentium III 1266S outperforms Pentium III 1400S by an impressive 58% based on our aggregate benchmark results.
Primary details
Comparing Pentium III 1266S and Pentium III 1400S processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 3243 | 3361 |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Desktop processor |
| Power efficiency | 0.60 | 0.35 |
| Architecture codename | Tualatin (2000−2002) | Tualatin (2000−2002) |
| Release date | July 2001 (23 years ago) | January 2002 (22 years ago) |
Detailed specifications
Pentium III 1266S and Pentium III 1400S 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 | 1.27 GHz | 1.4 GHz |
| L1 cache | 8 KB | 8 KB |
| L2 cache | 512 KB | 512 KB |
| L3 cache | 0 KB | 0 KB |
| Chip lithography | 130 nm | 130 nm |
| Die size | 80 mm2 | 80 mm2 |
| Maximum case temperature (TCase) | 69 °C | 69 °C |
| Number of transistors | 44 million | 44 million |
| 64 bit support | - | - |
| Windows 11 compatibility | - | - |
Compatibility
Information on Pentium III 1266S and Pentium III 1400S 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 | 370 | 370 |
| Power consumption (TDP) | 30 Watt | 32 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 | 0.19 | 0.12 |
| Power consumption (TDP) | 30 Watt | 32 Watt |
Pentium III 1266S has a 58.3% higher aggregate performance score, and 6.7% lower power consumption.
The Pentium III 1266S is our recommended choice as it beats the Pentium III 1400S in performance tests.
Should you still have questions on choice between Pentium III 1266S and Pentium III 1400S, ask them in Comments section, and we shall answer.
Similar processor comparisons
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