Athlon XP 1800+ vs Pentium III 1266S
General info
Comparing Pentium III 1266S and Athlon XP 1800+ processor market type (desktop or notebook), architecture, sales start time and price.
| Place in performance ranking | not rated | not rated |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Desktop processor |
| Architecture codename | Tualatin (2000−2002) | Thoroughbred (2001−2002) |
| Release date | July 2001 (22 years old) | January 2001 (23 years old) |
| Launch price (MSRP) | no data | $59 |
| Current price | no data | $54 (0.9x MSRP) |
Technical specs
Pentium III 1266S and Athlon XP 1800+ 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 | 1.53 GHz |
| L1 cache | 8 KB | 128 KB |
| L2 cache | 512 KB | 256 KB |
| L3 cache | 0 KB | 0 KB |
| Chip lithography | 130 nm | 180 nm |
| Die size | 80 mm2 | 150 mm2 |
| Maximum case temperature (TCase) | 69 °C | no data |
| Number of transistors | 44 million | 37 million |
| 64 bit support | - | - |
| Windows 11 compatibility | - | - |
| Unlocked multiplier | No | No |
Compatibility
Information on Pentium III 1266S and Athlon XP 1800+ 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 | A |
| Power consumption (TDP) | 30 Watt | 66 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.
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.
Benchmark coverage: 68%
Pentium III 1266S outperforms Athlon XP 1800+ by 58% in Passmark.
Advantages and disadvantages
| Chip lithography | 130 nm | 180 nm |
| Power consumption (TDP) | 30 Watt | 66 Watt |
We couldn't decide between Pentium III 1266S and Athlon XP 1800+. We've got no test results to judge.
Should you still have questions on choice between Pentium III 1266S and Athlon XP 1800+, ask them in Comments section, and we shall answer.
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