Athlon 850 vs Xeon E5645

Primary details

Comparing Xeon E5645 and Athlon 850 processor market type (desktop or notebook), architecture, sales start time and price.

Place in the ranking	1605	not rated
Place by popularity	not in top-100	not in top-100
Cost-effectiveness evaluation	1.38	no data
Market segment	Server	Desktop processor
Power efficiency	3.76	no data
Architecture codename	Westmere-EP (2010−2011)	Thunderbird (1999−2000)
Release date	16 March 2010 (14 years ago)	11 February 2000 (24 years ago)
Launch price (MSRP)	$294	$849

Cost-effectiveness evaluation

Performance per price, higher is better.

Detailed specifications

Xeon E5645 and Athlon 850 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	6 (Hexa-Core)	1 (Single-Core)
Threads	12	1
Base clock speed	2.4 GHz	no data
Boost clock speed	2.67 GHz	0.85 GHz
L1 cache	64 KB (per core)	128 KB
L2 cache	256 KB (per core)	512 KB
L3 cache	12 MB (shared)	0 KB
Chip lithography	32 nm	180 nm
Die size	239 mm2	102 mm2
Maximum core temperature	76 °C	no data
Maximum case temperature (TCase)	no data	70 °C
Number of transistors	1,170 million	22 million
64 bit support	+	-
Windows 11 compatibility	-	-

Compatibility

Information on Xeon E5645 and Athlon 850 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	FCLGA1366,LGA1366	A
Power consumption (TDP)	80 Watt	45 Watt

Technologies and extensions

Technological solutions and additional instructions supported by Xeon E5645 and Athlon 850. You'll probably need this information if you require some particular technology.

Instruction set extensions	Intel® SSE4.2	no data
AES-NI	+	-
Enhanced SpeedStep (EIST)	+	no data
Turbo Boost Technology	1.0	no data
Hyper-Threading Technology	+	no data
Idle States	+	no data
Demand Based Switching	+	no data
PAE	40 Bit	no data

Security technologies

Xeon E5645 and Athlon 850 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 Xeon E5645 and Athlon 850 are enumerated here.

VT-d	+	no data
VT-x	+	no data
EPT	+	no data

Memory specs

Types, maximum amount and channel quantity of RAM supported by Xeon E5645 and Athlon 850. Depending on the motherboard, higher memory frequencies may be supported.

Supported memory types	DDR3	DDR1
Maximum memory size	288 GB	no data
Max memory channels	3	no data
Maximum memory bandwidth	32 GB/s	no data
ECC memory support	+	-

Graphics specifications

General parameters of integrated GPUs, if any.

Integrated graphics card

no data

N/A

Peripherals

Specifications and connection of peripherals supported by Xeon E5645 and Athlon 850.

PCIe version

2.0

no data

Pros & cons summary

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Recency	16 March 2010	11 February 2000
Physical cores	6	1
Threads	12	1
Chip lithography	32 nm	180 nm
Power consumption (TDP)	80 Watt	45 Watt

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