Athlon 64 FX-55 vs Pentium D 820

Primary details

Comparing Pentium D 820 and Athlon 64 FX-55 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	3096	3160
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	0.23
Architecture codename	Smithfield (2005)	Clawhammer (2001−2005)
Release date	May 2005 (19 years ago)	10 October 2004 (20 years ago)
Launch price (MSRP)	no data	$180

Cost-effectiveness evaluation

Performance per price, higher is better.

Detailed specifications

Pentium D 820 and Athlon 64 FX-55 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	2.6 GHz
Boost clock speed	2.8 GHz	2.6 GHz
Bus rate	800 MHz	no data
L1 cache	28 KB	128 KB
L2 cache	2 MB	1 MB
L3 cache	0 KB	0 KB
Chip lithography	90 nm	130 nm
Die size	206 mm2	193 mm2
Maximum core temperature	64 °C	no data
Maximum case temperature (TCase)	no data	63 °C
Number of transistors	169 million	105 million
64 bit support	+	+
Windows 11 compatibility	-	-
Unlocked multiplier	-	+
VID voltage range	1.2V-1.4V	no data

Compatibility

Information on Pentium D 820 and Athlon 64 FX-55 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	939
Power consumption (TDP)	95 Watt	104 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Pentium D 820 and Athlon 64 FX-55. 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 Athlon 64 FX-55 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 Athlon 64 FX-55 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 Athlon 64 FX-55. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types

DDR1, DDR2, DDR3

DDR1 Depends on motherboard

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card

no data

On certain motherboards (Chipset feature)

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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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.

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Pros & cons summary

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Performance score	0.31	0.25
Physical cores	2	1
Threads	2	1
Chip lithography	90 nm	130 nm
Power consumption (TDP)	95 Watt	104 Watt

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Should you still have questions on choice between Pentium D 820 and Athlon 64 FX-55, ask them in Comments section, and we shall answer.

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