Athlon II X4 651K vs Athlon II X4 638
Primary details
Comparing Athlon II X4 638 and Athlon II X4 651K processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 2191 | not rated |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Desktop processor |
| Power efficiency | 2.06 | no data |
| Architecture codename | Llano (2011−2012) | Llano (2011−2012) |
| Release date | 6 February 2012 (12 years ago) | 14 November 2011 (13 years ago) |
Detailed specifications
Athlon II X4 638 and Athlon II X4 651K 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 | 4 (Quad-Core) | 4 (Quad-Core) |
| Threads | 4 | 4 |
| Base clock speed | 2.7 GHz | 3 GHz |
| Boost clock speed | 2.7 GHz | 3 GHz |
| L1 cache | 128 KB (per core) | 128 KB (per core) |
| L2 cache | 1 MB (per core) | 1 MB (per core) |
| L3 cache | 0 KB | 0 KB |
| Chip lithography | 32 nm | 32 nm |
| Die size | 228 mm2 | 228 mm2 |
| Number of transistors | 1,178 million | 1,178 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
Compatibility
Information on Athlon II X4 638 and Athlon II X4 651K 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 | FM1 | FM1 |
| Power consumption (TDP) | 65 Watt | 100 Watt |
Virtualization technologies
Virtual machine speed-up technologies supported by Athlon II X4 638 and Athlon II X4 651K are enumerated here.
| AMD-V | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Athlon II X4 638 and Athlon II X4 651K. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3 | DDR3 |
Pros & cons summary
| Recency | 6 February 2012 | 14 November 2011 |
| Power consumption (TDP) | 65 Watt | 100 Watt |
Athlon II X4 638 has an age advantage of 2 months, and 53.8% lower power consumption.
We couldn't decide between Athlon II X4 638 and Athlon II X4 651K. We've got no test results to judge.
Should you still have questions on choice between Athlon II X4 638 and Athlon II X4 651K, ask them in Comments section, and we shall answer.
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