Core 2 Quad Q9400 vs Xeon E5645
Aggregate performance score
Xeon E5645 outperforms Core 2 Quad Q9400 by a whopping 136% based on our aggregate benchmark results.
Primary details
Comparing Xeon E5645 and Core 2 Quad Q9400 processor market type (desktop or notebook), architecture, sales start time and price.
| Place in the ranking | 1618 | 2256 |
| Place by popularity | not in top-100 | not in top-100 |
| Cost-effectiveness evaluation | 1.38 | no data |
| Market segment | Server | Desktop processor |
| Power efficiency | 3.76 | 1.34 |
| Architecture codename | Westmere-EP (2010−2011) | Yorkfield (2007−2009) |
| Release date | 16 March 2010 (14 years ago) | August 2008 (16 years ago) |
| Launch price (MSRP) | $294 | no data |
Cost-effectiveness evaluation
Performance per price, higher is better.
Detailed specifications
Xeon E5645 and Core 2 Quad Q9400 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 | 6 (Hexa-Core) | 4 (Quad-Core) |
| Threads | 12 | 4 |
| Base clock speed | 2.4 GHz | 2.66 GHz |
| Boost clock speed | 2.67 GHz | 2.67 GHz |
| Bus rate | no data | 1333 MHz |
| L1 cache | 64 KB (per core) | 64K (per core) |
| L2 cache | 256 KB (per core) | 6 MB (shared) |
| L3 cache | 12 MB (shared) | 0 KB |
| Chip lithography | 32 nm | 45 nm |
| Die size | 239 mm2 | 2x 81 mm2 |
| Maximum core temperature | 76 °C | no data |
| Maximum case temperature (TCase) | no data | 71 °C |
| Number of transistors | 1,170 million | 456 million |
| 64 bit support | + | + |
| Windows 11 compatibility | - | - |
| VID voltage range | no data | 0.85V-1.3625V |
Compatibility
Information on Xeon E5645 and Core 2 Quad Q9400 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 | 2 | 1 |
| Socket | FCLGA1366,LGA1366 | LGA775 |
| Power consumption (TDP) | 80 Watt | 95 Watt |
Technologies and extensions
Technological solutions and additional instructions supported by Xeon E5645 and Core 2 Quad Q9400. You'll probably need this information if you require some particular technology.
| Instruction set extensions | Intel® SSE4.2 | no data |
| AES-NI | + | - |
| Enhanced SpeedStep (EIST) | + | + |
| Turbo Boost Technology | 1.0 | - |
| Hyper-Threading Technology | + | - |
| Idle States | + | + |
| Thermal Monitoring | - | + |
| Demand Based Switching | + | - |
| PAE | 40 Bit | no data |
| FSB parity | no data | - |
Security technologies
Xeon E5645 and Core 2 Quad Q9400 technologies aimed at improving security, for example, by protecting against hacks.
| TXT | + | + |
| EDB | + | + |
Virtualization technologies
Virtual machine speed-up technologies supported by Xeon E5645 and Core 2 Quad Q9400 are enumerated here.
| VT-d | + | + |
| VT-x | + | + |
| EPT | + | no data |
Memory specs
Types, maximum amount and channel quantity of RAM supported by Xeon E5645 and Core 2 Quad Q9400. Depending on the motherboard, higher memory frequencies may be supported.
| Supported memory types | DDR3 | DDR1, DDR2, DDR3 |
| Maximum memory size | 288 GB | no data |
| Max memory channels | 3 | no data |
| Maximum memory bandwidth | 32 GB/s | no data |
| ECC memory support | + | - |
Peripherals
Specifications and connection of peripherals supported by Xeon E5645 and Core 2 Quad Q9400.
| PCIe version | 2.0 | no data |
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 | 3.18 | 1.35 |
| Physical cores | 6 | 4 |
| Threads | 12 | 4 |
| Chip lithography | 32 nm | 45 nm |
| Power consumption (TDP) | 80 Watt | 95 Watt |
Xeon E5645 has a 135.6% higher aggregate performance score, 50% more physical cores and 200% more threads, a 40.6% more advanced lithography process, and 18.8% lower power consumption.
The Xeon E5645 is our recommended choice as it beats the Core 2 Quad Q9400 in performance tests.
Be aware that Xeon E5645 is a server/workstation processor while Core 2 Quad Q9400 is a desktop one.
Should you still have questions on choice between Xeon E5645 and Core 2 Quad Q9400, ask them in Comments section, and we shall answer.
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