Core 2 Quad Q8400 vs Pentium D 820

Primary details

Comparing Pentium D 820 and Core 2 Quad Q8400 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	not rated	2266
Place by popularity	not in top-100	not in top-100
Market segment	Desktop processor	Desktop processor
Series	Pentium D	no data
Power efficiency	no data	1.30
Architecture codename	Smithfield (2005)	Yorkfield (2007−2009)
Release date	May 2005 (19 years ago)	19 April 2009 (15 years ago)

Detailed specifications

Pentium D 820 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 cores	2 (Dual-core)	4 (Quad-Core)
Threads	2	4
Base clock speed	2.8 GHz	2.66 GHz
Boost clock speed	2.8 GHz	0.67 GHz
Bus rate	800 MHz	1333 MHz
L1 cache	28 KB	64 KB (per core)
L2 cache	2 MB	4 MB (shared)
L3 cache	0 KB	0 KB
Chip lithography	90 nm	45 nm
Die size	206 mm2	2x 82 mm2
Maximum core temperature	64 °C	no data
Maximum case temperature (TCase)	no data	71 °C
Number of transistors	169 million	456 million
64 bit support	+	+
Windows 11 compatibility	-	-
VID voltage range	1.2V-1.4V	0.85V-1.3625V

Compatibility

Information on Pentium D 820 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 configuration	2	1
Socket	PLGA775	FCLGA775,LGA775
Power consumption (TDP)	95 Watt	95 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Pentium D 820 and Core 2 Quad Q8400. 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	32 Bit	no data
FSB parity	-	-

Security technologies

Pentium D 820 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 Pentium D 820 and Core 2 Quad Q8400 are enumerated here.

VT-d	-	no data
VT-x	-	+

Memory specs

Types, maximum amount and channel quantity of RAM supported by Pentium D 820 and Core 2 Quad Q8400. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types

DDR1, DDR2, DDR3

DDR1, DDR2, DDR3

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card

no data

On certain motherboards (Chipset feature)

Peripherals

Specifications and connection of peripherals supported by Pentium D 820 and Core 2 Quad Q8400.

PCIe version

no data

2.0

Synthetic benchmark performance

Various benchmark results of the processors in comparison. Overall score is measured in points in 0-100 range, higher is better.

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Pros & cons summary

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Physical cores	2	4
Threads	2	4
Chip lithography	90 nm	45 nm

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Should you still have questions on choice between Pentium D 820 and Core 2 Quad Q8400, ask them in Comments section, and we shall answer.

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