GeForce GTX 660 OEM and GeForce 840M - video card comparison
GeForce GTX 660 OEM
GeForce 840M
Architecture
Kepler (2012−2018)
Maxwell (2014−2018)
GPU code name
GK104
N15S-GT
Market segment
Desktop
Laptop
Release date
August 2012
March 2014
Bus support
-
PCI Express 2.0, PCI Express 3.0
Interface
PCIe 3.0 x16
PCIe 3.0 x8
Supplementary power connectors
1x 6-pin
-
Boost clock speed
888 MHz
1124 MHz
Core clock speed
823 MHz
1029 MHz
Floating-point performance
2,046 gflops
863.2 gflops
Manufacturing process technology
28 nm
28 nm
Number of transistors
3,540 million
-
Pipelines / CUDA cores
1152
384
Power consumption (TDP)
130 Watt
33 Watt
Texture fill rate
85.25
17.98
Memory type
GDDR5
DDR3
Maximum RAM amount
2 GB
4 GB
Memory bus width
256 Bit
64 Bit
Memory clock speed
5600 MHz
2000 MHz
Memory bandwidth
179.2 GB/s
16.02 GB/s
Shared memory
-
-
Display Connectors
2x DVI, 1x HDMI, 1x DisplayPort
No outputs
HDMI
+
-
DirectX
12 (11_0)
12 (11_0)
CUDA
3.0
+
OpenCL
1.2
1.2
OpenGL
4.6
4.5
Shader Model
5.1
5.1
Vulkan
1.1.126
1.1.126
GameWorks
-
+
GPU Boost
-
2.0
Optimus
-
+