Pentium D 820 vs Core 2 Quad Q9400
Aggregate performance score
Core 2 Quad Q9400 outperforms Pentium D 820 by a whopping 332% based on our aggregate benchmark results.
Primary details
Comparing Core 2 Quad Q9400 and Pentium D 820 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 2243 | 3084 |
| Place by popularity | not in top-100 | not in top-100 |
| Market segment | Desktop processor | Desktop processor |
| Series | no data | Pentium D |
| Power efficiency | 1.33 | 0.31 |
| Architecture codename | Yorkfield (2007−2009) | Smithfield (2005) |
| Release date | August 2008 (16 years ago) | May 2005 (19 years ago) |
Detailed specifications
Core 2 Quad Q9400 and Pentium D 820 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) | 2 (Dual-core) |
| Threads | 4 | 2 |
| Base clock speed | 2.66 GHz | 2.8 GHz |
| Boost clock speed | 2.67 GHz | 2.8 GHz |
| Bus rate | 1333 MHz | 800 MHz |
| L1 cache | 64K (per core) | 28 KB |
| L2 cache | 6 MB (shared) | 2 MB |
| L3 cache | 0 KB | 0 KB |
| Chip lithography | 45 nm | 90 nm |
| Die size | 2x 81 mm2 | 206 mm2 |
| Maximum core temperature | no data | 64 °C |
| Maximum case temperature (TCase) | 71 °C | no data |
| Number of transistors | 456 million | 169 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
| VID voltage range | 0.85V-1.3625V | 1.2V-1.4V |
Compatibility
Information on Core 2 Quad Q9400 and Pentium D 820 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 | 2 |
| Socket | LGA775 | PLGA775 |
| Power consumption (TDP) | 95 Watt | 95 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Core 2 Quad Q9400 and Pentium D 820. You'll probably need this information if you require some particular technology.
| Enhanced SpeedStep (EIST) | + | - |
| Turbo Boost Technology | - | - |
| Hyper-Threading Technology | - | - |
| Idle States | + | + |
| Thermal Monitoring | + | - |
| Demand Based Switching | - | - |
| PAE | no data | 32 Bit |
| FSB parity | - | - |
Security technologies
Core 2 Quad Q9400 and Pentium D 820 technologies aimed at improving security, for example, by protecting against hacks.
| TXT | + | - |
| EDB | + | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Core 2 Quad Q9400 and Pentium D 820 are enumerated here.
| VT-d | + | - |
| VT-x | + | - |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Core 2 Quad Q9400 and Pentium D 820. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR1, DDR2, DDR3 | DDR1, DDR2, DDR3 |
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.
Pros & cons summary
| Performance score | 1.34 | 0.31 |
| Physical cores | 4 | 2 |
| Threads | 4 | 2 |
| Chip lithography | 45 nm | 90 nm |
Core 2 Quad Q9400 has a 332.3% higher aggregate performance score, 100% more physical cores and 100% more threads, and a 100% more advanced lithography process.
The Core 2 Quad Q9400 is our recommended choice as it beats the Pentium D 820 in performance tests.
Should you still have questions on choice between Core 2 Quad Q9400 and Pentium D 820, ask them in Comments section, and we shall answer.
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