GeForce GT 640 OEM Rebrand vs GTX 870M

Primary details

GPU architecture, market segment, value for money and other general parameters compared.

Place in the ranking	485	not rated
Place by popularity	not in top-100	not in top-100
Power efficiency	6.19	no data
Architecture	Kepler (2012−2018)	Fermi 2.0 (2010−2014)
GPU code name	GK104	GF116
Market segment	Laptop	Desktop
Release date	12 March 2014 (10 years ago)	24 April 2012 (12 years ago)

Detailed specifications

General parameters such as number of shaders, GPU core base clock and boost clock speeds, manufacturing process, texturing and calculation speed. Note that power consumption of some graphics cards can well exceed their nominal TDP, especially when overclocked.

Pipelines / CUDA cores	1344	144
Core clock speed	941 MHz	720 MHz
Boost clock speed	967 MHz	no data
Number of transistors	3,540 million	1,170 million
Manufacturing process technology	28 nm	40 nm
Power consumption (TDP)	100 Watt	75 Watt
Texture fill rate	108.3	17.28
Floating-point processing power	2.599 TFLOPS	0.4147 TFLOPS
ROPs	24	24
TMUs	112	24

Form factor & compatibility

Information on compatibility with other computer components. Useful when choosing a future computer configuration or upgrading an existing one. For desktop graphics cards it's interface and bus (motherboard compatibility), additional power connectors (power supply compatibility).

Laptop size	large	no data
Bus support	PCI Express 2.0, PCI Express 3.0	no data
Interface	MXM-B (3.0)	PCIe 2.0 x16
Length	no data	145 mm
Width	no data	1-slot
Supplementary power connectors	None	None
SLI options	+	-

VRAM capacity and type

Parameters of VRAM installed: its type, size, bus, clock and resulting bandwidth. Integrated GPUs have no dedicated video RAM and use a shared part of system RAM.

Memory type	GDDR5	DDR3
Maximum RAM amount	3 GB	1536 MB
Standard memory configuration	GDDR5	no data
Memory bus width	192 Bit	192 Bit
Memory clock speed	Up to 2500 MHz	800 MHz
Memory bandwidth	120.0 GB/s	38.4 GB/s
Shared memory	-	no data

Connectivity and outputs

Types and number of video connectors present on the reviewed GPUs. As a rule, data in this section is precise only for desktop reference ones (so-called Founders Edition for NVIDIA chips). OEM manufacturers may change the number and type of output ports, while for notebook cards availability of certain video outputs ports depends on the laptop model rather than on the card itself.

Display Connectors	No outputs	2x DVI, 1x mini-HDMI
eDP 1.2 signal support	Up to 3840x2160	no data
LVDS signal support	Up to 1920x1200	no data
VGA аnalog display support	Up to 2048x1536	no data
DisplayPort Multimode (DP++) support	Up to 3840x2160	no data
HDMI	+	+
HDCP content protection	+	-
7.1 channel HD audio on HDMI	+	-
TrueHD and DTS-HD audio bitstreaming	+	-

Supported technologies

Supported technological solutions. This information will prove useful if you need some particular technology for your purposes.

H.264, VC1, MPEG2 1080p video decoder	+	-
Optimus	+	-

API compatibility

List of supported 3D and general-purpose computing APIs, including their specific versions.

DirectX	12 (11_0)	12 (11_0)
Shader Model	5.1	5.1
OpenGL	4.5	4.6
OpenCL	1.1	1.1
Vulkan	1.1.126	N/A
CUDA	+	2.1

Pros & cons summary

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Recency	12 March 2014	24 April 2012
Maximum RAM amount	3 GB	1536 MB
Chip lithography	28 nm	40 nm
Power consumption (TDP)	100 Watt	75 Watt

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