Ultra 5 245KF vs Pentium III 1266S
Aggregate performance score
Core Ultra 5 245KF outperforms Pentium III 1266S by a whopping 14468% based on our aggregate benchmark results.
Primary details
Comparing Pentium III 1266S and Core Ultra 5 245KF processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 3242 | 176 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | no data | 82.57 |
| Market segment | Desktop processor | Desktop processor |
| Power efficiency | 0.60 | 20.96 |
| Architecture codename | Tualatin (2000−2002) | Arrow Lake-S (2024−2025) |
| Release date | July 2001 (23 years ago) | 24 October 2024 (less than a year ago) |
| Launch price (MSRP) | no data | $294 |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Pentium III 1266S and Core Ultra 5 245KF 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) | 14 (Tetradeca-Core) |
| Threads | 1 | 14 |
| Base clock speed | no data | 4.2 GHz |
| Boost clock speed | 1.27 GHz | 5.2 GHz |
| L1 cache | 8 KB | 112 KB (per core) |
| L2 cache | 512 KB | 3 MB (per core) |
| L3 cache | 0 KB | 24 MB (shared) |
| Chip lithography | 130 nm | 3 nm |
| Die size | 80 mm2 | 243 mm2 |
| Maximum case temperature (TCase) | 69 °C | no data |
| Number of transistors | 44 million | 17,800 million |
| 64 bit support | - | + |
| Windows 11 compatibility | - | no data |
Compatibility
Information on Pentium III 1266S and Core Ultra 5 245KF 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 | FCLGA1851 |
| Power consumption (TDP) | 30 Watt | 125 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Pentium III 1266S and Core Ultra 5 245KF. You'll probably need this information if you require some particular technology.
| Instruction set extensions | no data | Intel® SSE4.1, Intel® SSE4.2, Intel® AVX2 |
| AES-NI | - | + |
| AVX | - | + |
| Enhanced SpeedStep (EIST) | no data | + |
| Speed Shift | no data | + |
| Turbo Boost Technology | no data | 2.0 |
| TSX | - | + |
| Idle States | no data | + |
| Thermal Monitoring | - | + |
| Deep Learning Boost | - | + |
| Supported AI Software Frameworks | - | OpenVINO™, WindowsML, DirectML, ONNX RT, WebNN |
Security technologies
Pentium III 1266S and Core Ultra 5 245KF technologies aimed at improving security, for example, by protecting against hacks.
| TXT | no data | + |
| EDB | no data | + |
| Secure Key | no data | + |
| OS Guard | no data | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Pentium III 1266S and Core Ultra 5 245KF are enumerated here.
| VT-d | no data | + |
| VT-x | no data | + |
| EPT | no data | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Pentium III 1266S and Core Ultra 5 245KF. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | no data | DDR5-6400 |
| Maximum memory size | no data | 192 GB |
| Max memory channels | no data | 2 |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | no data | N/A |
Peripherals
Specifications and connection of peripherals supported by Pentium III 1266S and Core Ultra 5 245KF.
| PCIe version | no data | 5.0 and 4.0 |
| PCI Express lanes | no data | 20 |
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 | 27.68 |
| Physical cores | 1 | 14 |
| Threads | 1 | 14 |
| Chip lithography | 130 nm | 3 nm |
| Power consumption (TDP) | 30 Watt | 125 Watt |
Pentium III 1266S has 316.7% lower power consumption.
Ultra 5 245KF, on the other hand, has a 14468.4% higher aggregate performance score, 1300% more physical cores and 1300% more threads, and a 4233.3% more advanced lithography process.
The Core Ultra 5 245KF is our recommended choice as it beats the Pentium III 1266S in performance tests.
Should you still have questions on choice between Pentium III 1266S and Core Ultra 5 245KF, ask them in Comments section, and we shall answer.
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