Pentium 4 HT 651 vs Pentium 4 HT 640
Primary details
Comparing Pentium 4 HT 640 and Pentium 4 HT 651 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | not rated | not rated |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Desktop processor |
| Architecture codename | Prescott (2001−2005) | Cedar Mill (2006) |
| Release date | February 2005 (19 years ago) | January 2006 (18 years ago) |
Detailed specifications
Pentium 4 HT 640 and Pentium 4 HT 651 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 | 2 | 2 |
| Boost clock speed | 3.2 GHz | 3.4 GHz |
| L1 cache | 28 KB | 28 KB |
| L2 cache | 2 MB | 2 MB |
| L3 cache | 0 KB | 0 KB |
| Chip lithography | 90 nm | 65 nm |
| Die size | 109 mm2 | 81 mm2 |
| Number of transistors | 169 million | 188 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
Compatibility
Information on Pentium 4 HT 640 and Pentium 4 HT 651 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 | 775 | 775 |
| Power consumption (TDP) | 84 Watt | 86 Watt |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Pentium 4 HT 640 and Pentium 4 HT 651. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR1, DDR2, DDR3 | DDR1, DDR2, DDR3 |
Pros & cons summary
| Chip lithography | 90 nm | 65 nm |
| Power consumption (TDP) | 84 Watt | 86 Watt |
Pentium 4 HT 640 has 2.4% lower power consumption.
Pentium 4 HT 651, on the other hand, has a 38.5% more advanced lithography process.
We couldn't decide between Pentium 4 HT 640 and Pentium 4 HT 651. We've got no test results to judge.
Should you still have questions on choice between Pentium 4 HT 640 and Pentium 4 HT 651, ask them in Comments section, and we shall answer.
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