GeForce GT 640 and GeForce 820M - video card comparison
Passmark - benchmark score GeForce GT 640 vs GeForce 820M
GeForce GT 640
1209
GeForce 820M
511
GeForce GT 640
GeForce 820M
Architecture
Kepler (2012−2018)
Fermi (2010−2014)
GPU code name
GK107
N15V-GM
Market segment
Desktop
Laptop
Release date
June 2012
January 2014
Bus support
-
PCI Express 2.0
Interface
PCIe 3.0 x16
PCIe 2.0 x16
Supplementary power connectors
None
-
Core clock speed
902 MHz
775 MHz
Floating-point performance
692.7 gflops
240.0 gflops
Manufacturing process technology
28 nm
28 nm
Number of transistors
1,270 million
585 million
Pipelines / CUDA cores
384
96
Power consumption (TDP)
65 Watt
15 Watt
Texture fill rate
28.86
10.00
Memory type
DDR3
DDR3
Maximum RAM amount
2 GB
2 GB
Memory bus width
128 Bit
64 Bit
Memory clock speed
1782 MHz
1800 MHz
Memory bandwidth
28.51 GB/s
14.4 GB/s
Shared memory
-
-
Display Connectors
1x DVI, 1x HDMI, 1x DisplayPort
No outputs
HDMI
+
-
DirectX
12 (11_0)
12 (11_0)
CUDA
3.0
+
OpenCL
1.2
1.1
OpenGL
4.6
4.5
Shader Model
5.1
5.1
Vulkan
1.1.126
N/A
GameWorks
-
+
GPU Boost
-
2.0
Optimus
-
+