Athlon II X4 645 vs Phenom II X2 555 BE
Primary details
Comparing Phenom II X2 555 BE and Athlon II X4 645 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | not rated | 2152 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | no data | 3.30 |
| Market segment | Desktop processor | Desktop processor |
| Power efficiency | no data | 1.47 |
| Architecture codename | Callisto (2009−2010) | Propus (2009−2011) |
| Release date | 25 January 2010 (14 years ago) | 21 September 2010 (14 years ago) |
| Launch price (MSRP) | no data | $80 |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Phenom II X2 555 BE and Athlon II X4 645 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 | 2 (Dual-core) | 4 (Quad-Core) |
| Threads | 2 | 4 |
| Base clock speed | 3.2 GHz | 3.1 GHz |
| Boost clock speed | 3.2 GHz | 3.1 GHz |
| L1 cache | 128 KB (per core) | 128 KB (per core) |
| L2 cache | 512 KB (per core) | 512 KB (per core) |
| L3 cache | 6 MB (shared) | 0 KB |
| Chip lithography | 45 nm | 45 nm |
| Die size | 258 mm2 | 169 mm2 |
| Number of transistors | 758 million | 300 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
| Unlocked multiplier | + | - |
Compatibility
Information on Phenom II X2 555 BE and Athlon II X4 645 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 | AM3 | AM3 |
| Power consumption (TDP) | 80 Watt | 95 Watt |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Phenom II X2 555 BE and Athlon II X4 645. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3 | DDR3 |
Peripherals
Specifications and connection of peripherals supported by Phenom II X2 555 BE and Athlon II X4 645.
| PCIe version | 2.0 | 2.0 |
Pros & cons summary
| Recency | 25 January 2010 | 21 September 2010 |
| Physical cores | 2 | 4 |
| Threads | 2 | 4 |
| Power consumption (TDP) | 80 Watt | 95 Watt |
Phenom II X2 555 BE has 18.8% lower power consumption.
Athlon II X4 645, on the other hand, has an age advantage of 7 months, and 100% more physical cores and 100% more threads.
We couldn't decide between Phenom II X2 555 BE and Athlon II X4 645. We've got no test results to judge.
Should you still have questions on choice between Phenom II X2 555 BE and Athlon II X4 645, ask them in Comments section, and we shall answer.
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