Core i7-840QM vs Core 2 Duo E8400
Aggregate performance score
Core i7-840QM outperforms Core 2 Duo E8400 by an impressive 67% based on our aggregate benchmark results.
Primary details
Comparing Core 2 Duo E8400 and Core i7-840QM processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 2668 | 2308 |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Laptop |
| Series | no data | Intel Core i7 |
| Power efficiency | 1.07 | 2.58 |
| Architecture codename | Wolfdale (2008−2010) | Clarksfield (2009−2010) |
| Release date | 1 January 2008 (16 years ago) | 22 June 2010 (14 years ago) |
| Launch price (MSRP) | no data | $568 |
Detailed specifications
Core 2 Duo E8400 and Core i7-840QM 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 | 8 |
| Base clock speed | 3 GHz | 1.86 GHz |
| Boost clock speed | 3 GHz | 3.2 GHz |
| Bus type | no data | DMI 1.0 |
| Bus rate | 1333 MHz | 2.5 GT/s |
| Multiplier | no data | 14 |
| L1 cache | 64 KB (per core) | 256 KB |
| L2 cache | 6 MB (shared) | 1 MB |
| L3 cache | 0 KB | 8 MB (shared) |
| Chip lithography | 45 nm | 45 nm |
| Die size | 104 mm2 | 296 mm2 |
| Maximum core temperature | no data | 100 °C |
| Maximum case temperature (TCase) | 72 °C | no data |
| Number of transistors | 410 million | 774 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
| VID voltage range | 0.85V-1.3625V | no data |
Compatibility
Information on Core 2 Duo E8400 and Core i7-840QM 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 (Uniprocessor) |
| Socket | LGA775 | FCPGA988,PGA988 |
| Power consumption (TDP) | 65 Watt | 45 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Core 2 Duo E8400 and Core i7-840QM. You'll probably need this information if you require some particular technology.
| Instruction set extensions | no data | Intel® SSE4.2 |
| vPro | no data | + |
| Enhanced SpeedStep (EIST) | + | + |
| Turbo Boost Technology | - | + |
| Hyper-Threading Technology | - | + |
| Idle States | + | + |
| Thermal Monitoring | + | + |
| Demand Based Switching | - | no data |
| PAE | no data | 36 Bit |
| FSB parity | - | no data |
Security technologies
Core 2 Duo E8400 and Core i7-840QM technologies aimed at improving security, for example, by protecting against hacks.
| TXT | + | + |
| EDB | + | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Core 2 Duo E8400 and Core i7-840QM are enumerated here.
| VT-d | + | + |
| VT-x | + | + |
| EPT | no data | + |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Core 2 Duo E8400 and Core i7-840QM. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR1, DDR2, DDR3 | DDR3 |
| Maximum memory size | no data | 8 GB |
| Max memory channels | no data | 2 |
| Maximum memory bandwidth | no data | 21.335 GB/s |
Graphics specifications
General parameters of integrated GPUs, if any.
| Integrated graphics card | On certain motherboards (Chipset feature) | None |
Peripherals
Specifications and connection of peripherals supported by Core 2 Duo E8400 and Core i7-840QM.
| PCIe version | 2.0 | 2 |
| PCI Express lanes | no data | 16 |
Synthetic benchmark performance
Various benchmark results of the processors in comparison. Overall score is measured in points in 0-100 range, higher is better.
Combined synthetic benchmark score
This is our combined benchmark performance rating. We are regularly improving our combining algorithms, but if you find some perceived inconsistencies, feel free to speak up in comments section, we usually fix problems quickly.
Passmark
Passmark CPU Mark is a widespread benchmark, consisting of 8 different types of workload, including integer and floating point math, extended instructions, compression, encryption and physics calculation. There is also one separate single-threaded scenario measuring single-core performance.
GeekBench 5 Single-Core
GeekBench 5 Single-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses only a single CPU core.
GeekBench 5 Multi-Core
GeekBench 5 Multi-Core is a cross-platform application developed in the form of CPU tests that independently recreate certain real-world tasks with which to accurately measure performance. This version uses all available CPU cores.
Pros & cons summary
| Performance score | 0.75 | 1.25 |
| Recency | 1 January 2008 | 22 June 2010 |
| Physical cores | 2 | 4 |
| Threads | 2 | 8 |
| Power consumption (TDP) | 65 Watt | 45 Watt |
i7-840QM has a 66.7% higher aggregate performance score, an age advantage of 2 years, 100% more physical cores and 300% more threads, and 44.4% lower power consumption.
The Core i7-840QM is our recommended choice as it beats the Core 2 Duo E8400 in performance tests.
Note that Core 2 Duo E8400 is a desktop processor while Core i7-840QM is a notebook one.
Should you still have questions on choice between Core 2 Duo E8400 and Core i7-840QM, ask them in Comments section, and we shall answer.
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