Pentium III 866 vs Pentium D 820

Primary details

Comparing Pentium D 820 and Pentium III 866 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	3101	not rated
Place by popularity	not in top-100	not in top-100
Market segment	Desktop processor	Desktop processor
Series	Pentium D	no data
Power efficiency	0.31	no data
Architecture codename	Smithfield (2005)	Coppermine T (2000)
Release date	May 2005 (19 years ago)	20 March 2000 (24 years ago)

Detailed specifications

Pentium D 820 and Pentium III 866 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)	1 (Single-Core)
Threads	2	1
Base clock speed	2.8 GHz	no data
Boost clock speed	2.8 GHz	0.87 GHz
Bus rate	800 MHz	no data
L1 cache	28 KB	32 KB
L2 cache	2 MB	256 KB
L3 cache	0 KB	0 KB
Chip lithography	90 nm	180 nm
Die size	206 mm2	106 mm2
Maximum core temperature	64 °C	no data
Maximum case temperature (TCase)	no data	80 °C
Number of transistors	169 million	28 million
64 bit support	+	-
Windows 11 compatibility	-	-
VID voltage range	1.2V-1.4V	no data

Compatibility

Information on Pentium D 820 and Pentium III 866 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	2
Socket	PLGA775	370
Power consumption (TDP)	95 Watt	27 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Pentium D 820 and Pentium III 866. You'll probably need this information if you require some particular technology.

Enhanced SpeedStep (EIST)	-	no data
Turbo Boost Technology	-	no data
Hyper-Threading Technology	-	no data
Idle States	+	no data
Demand Based Switching	-	no data
PAE	32 Bit	no data
FSB parity	-	no data

Security technologies

Pentium D 820 and Pentium III 866 technologies aimed at improving security, for example, by protecting against hacks.

TXT	-	no data
EDB	+	no data

Virtualization technologies

Virtual machine speed-up technologies supported by Pentium D 820 and Pentium III 866 are enumerated here.

VT-d	-	no data
VT-x	-	no data

Memory specs

Types, maximum amount and channel quantity of RAM supported by Pentium D 820 and Pentium III 866. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types

DDR1, DDR2, DDR3

no data

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card

no data

On certain motherboards (Chipset feature)

Pros & cons summary

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Physical cores	2	1
Threads	2	1
Chip lithography	90 nm	180 nm
Power consumption (TDP)	95 Watt	27 Watt

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