Athlon II X4 651K vs Athlon X4 840
Primary details
Comparing Athlon X4 840 and Athlon II X4 651K processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 1874 | not rated |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Desktop processor |
| Series | 4x Athlon | no data |
| Power efficiency | 3.04 | no data |
| Architecture codename | Kaveri (2014−2015) | Llano (2011−2012) |
| Release date | August 2014 (10 years ago) | 14 November 2011 (13 years ago) |
Detailed specifications
Athlon X4 840 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 | 3.1 GHz | 3 GHz |
| Boost clock speed | 3.8 GHz | 3 GHz |
| L1 cache | 256K | 128 KB (per core) |
| L2 cache | 4 MB | 1 MB (per core) |
| L3 cache | no data | 0 KB |
| Chip lithography | 28 nm | 32 nm |
| Die size | 245 mm2 | 228 mm2 |
| Maximum case temperature (TCase) | 72 °C | no data |
| Number of transistors | 2,411 million | 1,178 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
| Unlocked multiplier | + | - |
Compatibility
Information on Athlon X4 840 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 | Socket FM2+ | FM1 |
| Power consumption (TDP) | 65 watt | 100 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Athlon X4 840 and Athlon II X4 651K. You'll probably need this information if you require some particular technology.
| AES-NI | + | - |
| FMA | + | - |
| AVX | + | - |
Virtualization technologies
Virtual machine speed-up technologies supported by Athlon X4 840 and Athlon II X4 651K are enumerated here.
| AMD-V | + | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Athlon X4 840 and Athlon II X4 651K. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3 | DDR3 |
Peripherals
Specifications and connection of peripherals supported by Athlon X4 840 and Athlon II X4 651K.
| PCIe version | 3.0 | no data |
| PCI Express lanes | 16 | no data |
Pros & cons summary
| Recency | on August 2014 | 14 November 2011 |
| Chip lithography | 28 nm | 32 nm |
| Power consumption (TDP) | 65 Watt | 100 Watt |
Athlon X4 840 has an age advantage of 2 years, a 14.3% more advanced lithography process, and 53.8% lower power consumption.
We couldn't decide between Athlon X4 840 and Athlon II X4 651K. We've got no test results to judge.
Should you still have questions on choice between Athlon X4 840 and Athlon II X4 651K, ask them in Comments section, and we shall answer.
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