Intel Pentium D 840 vs Intel Pentium III 866

Comparative analysis of Intel Pentium D 840 and Intel Pentium III 866 processors for all known characteristics in the following categories: Essentials, Performance, Memory, Compatibility, Security & Reliability, Advanced Technologies, Virtualization. Benchmark processor performance analysis: Geekbench 4 - Single Core, Geekbench 4 - Multi-Core, PassMark - Single thread mark, PassMark - CPU mark.

Intel Pentium D 840

Intel Pentium III 866

Differences

Reasons to consider the Intel Pentium D 840

1 more cores, run more applications at once: 2 vs 1
Around 268% higher clock speed: 3.2 GHz vs 0.87 GHz
A newer manufacturing process allows for a more powerful, yet cooler running processor: 90 nm vs 180 nm
3.5x more L1 cache, more data can be stored in the L1 cache for quick access later
8x more L2 cache, more data can be stored in the L2 cache for quick access later

Number of cores	2 vs 1
Maximum frequency	3.2 GHz vs 0.87 GHz
Manufacturing process technology	90 nm vs 180 nm
L1 cache	28 KB vs 8 KB
L2 cache	2048 KB vs 256 KB
Max number of CPUs in a configuration	2 vs 1

Reasons to consider the Intel Pentium III 866

Around 15% higher maximum core temperature: 80°C vs 69.8°C
5x lower typical power consumption: 26.1 Watt vs 130 Watt

Maximum core temperature	80°C vs 69.8°C
Thermal Design Power (TDP)	26.1 Watt vs 130 Watt

Compare benchmarks

CPU 1: Intel Pentium D 840
CPU 2: Intel Pentium III 866

Name	Intel Pentium D 840	Intel Pentium III 866
Geekbench 4 - Single Core	186
Geekbench 4 - Multi-Core	309
PassMark - Single thread mark		202
PassMark - CPU mark		152

Compare specifications (specs)

	Intel Pentium D 840	Intel Pentium III 866
Essentials
Architecture codename	Smithfield	Coppermine T
Launch date	May 2005	Q1'00
Place in performance rating	3298	3303
Processor Number	840
Series	Legacy Intel® Pentium® Processor	Legacy Intel® Pentium® Processor
Status	Discontinued	Discontinued
Vertical segment	Desktop	Desktop
Performance
64 bit support
Base frequency	3.20 GHz	866 MHz
Bus Speed	800 MHz FSB	133 MHz FSB
Die size	206 mm2	80 mm
L1 cache	28 KB	8 KB
L2 cache	2048 KB	256 KB
Manufacturing process technology	90 nm	180 nm
Maximum core temperature	69.8°C	80°C
Maximum frequency	3.2 GHz	0.87 GHz
Number of cores	2	1
Transistor count	230 million	44 million
VID voltage range	1.200V-1.400V	1.75V
Maximum case temperature (TCase)		69 °C
Memory
Supported memory types	DDR1, DDR2, DDR3
Compatibility
Low Halogen Options Available
Max number of CPUs in a configuration	2	1
Package Size	37.5mm x 37.5mm
Sockets supported	PLGA775	PPGA370, SECC2, SECC2495
Thermal Design Power (TDP)	130 Watt	26.1 Watt
Security & Reliability
Execute Disable Bit (EDB)
Intel® Trusted Execution technology (TXT)
Advanced Technologies
Enhanced Intel SpeedStep® technology
FSB parity
Idle States
Intel 64
Intel® AES New Instructions
Intel® Demand Based Switching
Intel® Hyper-Threading technology
Intel® Turbo Boost technology
Physical Address Extensions (PAE)	32-bit
Thermal Monitoring
Virtualization
Intel® Virtualization Technology (VT-x)
Intel® Virtualization Technology for Directed I/O (VT-d)