Core 2 Quad Q8400 vs Core i5-655K

Aggregate performance score

Core i5-655K
2010
2 cores / 4 threads, 73 Watt
1.27
Core 2 Quad Q8400
2009
4 cores / 4 threads, 95 Watt
1.30
+2.4%

Core 2 Quad Q8400 outperforms Core i5-655K by a minimal 2% based on our aggregate benchmark results.

Primary details

Comparing Core i5-655K and Core 2 Quad Q8400 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking22862268
Place by popularitynot in top-100not in top-100
Market segmentDesktop processorDesktop processor
Power efficiency1.651.30
Architecture codenameClarkdale (2010−2011)Yorkfield (2007−2009)
Release date30 May 2010 (14 years ago)19 April 2009 (15 years ago)

Detailed specifications

Core i5-655K and Core 2 Quad Q8400 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 cores2 (Dual-core)4 (Quad-Core)
Threads44
Base clock speed3.2 GHz2.66 GHz
Boost clock speed3.46 GHz0.67 GHz
Bus rate2.5 GT/s1333 MHz
L1 cache64 KB (per core)64 KB (per core)
L2 cache256 KB (per core)4 MB (shared)
L3 cache4 MB (shared)0 KB
Chip lithography32 nm45 nm
Die size81 mm22x 82 mm2
Maximum core temperature73 °Cno data
Maximum case temperature (TCase)no data71 °C
Number of transistors382 million456 million
64 bit support++
Windows 11 compatibility--
Unlocked multiplier+-
VID voltage rangeno data0.85V-1.3625V

Compatibility

Information on Core i5-655K and Core 2 Quad Q8400 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 configuration11
SocketFCLGA1156FCLGA775,LGA775
Power consumption (TDP)73 Watt95 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Core i5-655K and Core 2 Quad Q8400. You'll probably need this information if you require some particular technology.

Instruction set extensionsIntel® SSE4.2no data
AES-NI+-
Enhanced SpeedStep (EIST)++
Turbo Boost Technology1.0-
Hyper-Threading Technology+-
Idle States++
Thermal Monitoring-+
Demand Based Switching--
PAE36 Bitno data
FDI+no data
FSB parityno data-

Security technologies

Core i5-655K and Core 2 Quad Q8400 technologies aimed at improving security, for example, by protecting against hacks.

TXT+-
EDB++

Virtualization technologies

Virtual machine speed-up technologies supported by Core i5-655K and Core 2 Quad Q8400 are enumerated here.

VT-d+no data
VT-x++
EPT+no data

Memory specs

Types, maximum amount and channel quantity of RAM supported by Core i5-655K and Core 2 Quad Q8400. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory typesDDR3DDR1, DDR2, DDR3
Maximum memory size16.38 GBno data
Max memory channels2no data
Maximum memory bandwidth21 GB/sno data

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics cardIntel® HD Graphics for Previous Generation Intel® ProcessorsOn certain motherboards (Chipset feature)
Clear Video HD+no data

Graphics interfaces

Available interfaces and connections of Core i5-655K and Core 2 Quad Q8400 integrated GPUs.

Number of displays supported2no data

Peripherals

Specifications and connection of peripherals supported by Core i5-655K and Core 2 Quad Q8400.

PCIe version2.02.0
PCI Express lanes16no 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.

i5-655K 1.27
Core 2 Quad Q8400 1.30
+2.4%

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.

i5-655K 2017
Core 2 Quad Q8400 2067
+2.5%

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.

i5-655K 537
+63.7%
Core 2 Quad Q8400 328

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.

i5-655K 1247
+39.2%
Core 2 Quad Q8400 896

Gaming performance

Pros & cons summary


Performance score 1.27 1.30
Recency 30 May 2010 19 April 2009
Physical cores 2 4
Chip lithography 32 nm 45 nm
Power consumption (TDP) 73 Watt 95 Watt

i5-655K has an age advantage of 1 year, a 40.6% more advanced lithography process, and 30.1% lower power consumption.

Core 2 Quad Q8400, on the other hand, has a 2.4% higher aggregate performance score, and 100% more physical cores.

Given the minimal performance differences, no clear winner can be declared between Core i5-655K and Core 2 Quad Q8400.


Should you still have questions on choice between Core i5-655K and Core 2 Quad Q8400, ask them in Comments section, and we shall answer.

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Intel Core i5-655K
Core i5-655K
Intel Core 2 Quad Q8400
Core 2 Quad Q8400

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Community ratings

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Questions & comments

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