Athlon II X2 255 vs Phenom II X4 820

Primary details

Comparing Phenom II X4 820 and Athlon II X2 255 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	2254	2659
Place by popularity	not in top-100	not in top-100
Cost-effectiveness evaluation	2.10	0.02
Market segment	Desktop processor	Desktop processor
Power efficiency	1.31	1.08
Architecture codename	Deneb (2009−2011)	Regor (2009−2013)
Release date	1 September 2009 (15 years ago)	25 January 2010 (14 years ago)
Launch price (MSRP)	$90	$60

Cost-effectiveness evaluation

Performance per price, higher is better.

Phenom II X4 820 has 10400% better value for money than Athlon II X2 255.

Detailed specifications

Phenom II X4 820 and Athlon II X2 255 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	4 (Quad-Core)	2 (Dual-core)
Threads	4	2
Base clock speed	2.8 GHz	3.1 GHz
Boost clock speed	2.8 GHz	3.1 GHz
L1 cache	128 KB (per core)	128 KB
L2 cache	512 KB (per core)	1 MB
L3 cache	4 MB (shared)	0 KB
Chip lithography	45 nm	45 nm
Die size	258 mm2	117 mm2
Number of transistors	758 million	410 million
64 bit support	+	+
Windows 11 compatibility	-	-

Compatibility

Information on Phenom II X4 820 and Athlon II X2 255 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	1	1
Socket	AM3	AM3
Power consumption (TDP)	95 Watt	65 Watt

Virtualization technologies

Virtual machine speed-up technologies supported by Phenom II X4 820 and Athlon II X2 255 are enumerated here.

AMD-V

+

-

Memory specs

Types, maximum amount and channel quantity of RAM supported by Phenom II X4 820 and Athlon II X2 255. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types

DDR3

DDR3

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card

On certain motherboards (Chipset feature)

no data

Peripherals

Specifications and connection of peripherals supported by Phenom II X4 820 and Athlon II X2 255.

PCIe version

2.0

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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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	1.36	0.77
Recency	1 September 2009	25 January 2010
Physical cores	4	2
Threads	4	2
Power consumption (TDP)	95 Watt	65 Watt

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Should you still have questions on choice between Phenom II X4 820 and Athlon II X2 255, ask them in Comments section, and we shall answer.

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