Phenom II X3 P820 vs Athlon II X4 645
Aggregate performance score
Athlon II X4 645 outperforms Phenom II X3 P820 by a whopping 124% based on our aggregate benchmark results.
Primary details
Comparing Athlon II X4 645 and Phenom II X3 P820 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 2155 | 2740 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 3.30 | no data |
| Market segment | Desktop processor | Laptop |
| Series | no data | 3x AMD Phenom II |
| Power efficiency | 1.47 | 2.50 |
| Architecture codename | Propus (2009−2011) | Champlain (2010−2011) |
| Release date | 21 September 2010 (14 years ago) | 12 May 2010 (14 years ago) |
| Launch price (MSRP) | $80 | no data |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Athlon II X4 645 and Phenom II X3 P820 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) | 3 (Tri-Core) |
| Threads | 4 | 3 |
| Base clock speed | 3.1 GHz | no data |
| Boost clock speed | 3.1 GHz | 1.8 GHz |
| Bus rate | no data | 3600 MHz |
| L1 cache | 128 KB (per core) | 384 KB |
| L2 cache | 512 KB (per core) | 1.5 MB |
| L3 cache | 0 KB | no data |
| Chip lithography | 45 nm | 45 nm |
| Die size | 169 mm2 | no data |
| Number of transistors | 300 million | no data |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
Compatibility
Information on Athlon II X4 645 and Phenom II X3 P820 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 | no data |
| Socket | AM3 | S1 |
| Power consumption (TDP) | 95 Watt | 25 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Athlon II X4 645 and Phenom II X3 P820. You'll probably need this information if you require some particular technology.
| Instruction set extensions | no data | Virtualization, AMD64, Advanced Virus Protection, SSE(1,2,3,4a) |
| VirusProtect | - | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Athlon II X4 645 and Phenom II X3 P820 are enumerated here.
| AMD-V | - | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Athlon II X4 645 and Phenom II X3 P820. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3 | DDR3 |
Peripherals
Specifications and connection of peripherals supported by Athlon II X4 645 and Phenom II X3 P820.
| PCIe version | 2.0 | no data |
Pros & cons summary
| Performance score | 1.48 | 0.66 |
| Recency | 21 September 2010 | 12 May 2010 |
| Physical cores | 4 | 3 |
| Threads | 4 | 3 |
| Power consumption (TDP) | 95 Watt | 25 Watt |
Athlon II X4 645 has a 124.2% higher aggregate performance score, an age advantage of 4 months, and 33.3% more physical cores and 33.3% more threads.
Phenom II X3 P820, on the other hand, has 280% lower power consumption.
The Athlon II X4 645 is our recommended choice as it beats the Phenom II X3 P820 in performance tests.
Note that Athlon II X4 645 is a desktop processor while Phenom II X3 P820 is a notebook one.
Should you still have questions on choice between Athlon II X4 645 and Phenom II X3 P820, ask them in Comments section, and we shall answer.
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