GeForce 940MX vs GeForce GT 645M

In this comparison between GeForce 940MX and GeForce GT 645M you will find out which graphics card performs better in today's games. Bear in mind that third-party versions may have more efficient cooling and higher clock speeds. This will increase cards' performance, though not by much. In addition to raw power you should also take into account the dimensions. Thicker models simply will not fit into a small mini-ITX case. The resolution of your monitor also affects the choice, since 4K gameplay requires a more powerful GPU. And don't overspend on the graphics card. Other parts of your build may also need to be upgraded, save some money for the CPU or power supply. For some people GeForce 940MX will be the best choice, for others GeForce GT 645M will be their preference. Study the comparison tables below and make your choice.

GeForce 940MX and GeForce GT 645M are Laptop Graphics Cards

Note: GeForce 940MX and GeForce GT 645M are only used in laptop graphics. They have lower GPU clock speed compared to the desktop variant, which results in lower power consumption, but also 10-30% lower gaming performance. Check available laptop models with GeForce 940MX or GeForce GT 645M here:

Main Specs

  GeForce 940MX GeForce GT 645M
Power consumption (TDP) 23 Watt 32 Watt
Interface PCIe 3.0 x8 PCIe 3.0 x16
Supplementary power connectors None
Memory type DDR3, GDDR5 DDR3\GDDR5
Maximum RAM amount 4 GB 2 GB
Display Connectors No outputs No outputs
  Check Price Check Price
  • GeForce GT 645M has 39% more power consumption, than GeForce 940MX.
  • GeForce 940MX is connected by PCIe 3.0 x8, and GeForce GT 645M uses PCIe 3.0 x16 interface.
  • GeForce 940MX has 2 GB more memory, than GeForce GT 645M.
  • Both cards are used in Laptops.
  • GeForce 940MX is build with Maxwell architecture, and GeForce GT 645M - with Kepler.
  • GeForce 940MX and GeForce GT 645M are manufactured by 28 nm process technology.
  • Memory clock speed of GeForce 940MX is 2200 MHz higher, than GeForce GT 645M.

Game benchmarks

high / 1080p 7−8 1−2
ultra / 1080p 4−5 0−1
QHD / 1440p 0−1 0−1
low / 720p 16−18 12−14
medium / 1080p 8−9 2−3
The average gaming FPS of GeForce 940MX in Assassin's Creed Odyssey is 120% more, than GeForce GT 645M.

Full Specs

  GeForce 940MX GeForce GT 645M
Architecture Maxwell Kepler
Code name N16S-GTR-B/S N13P-GS
Type Laptop Laptop
Release date 10 March 2016 22 March 2012
Pipelines 384 384
Core clock speed 1122 MHz
Boost Clock 1242 MHz
Transistor count 1,870 million 1,270 million
Manufacturing process technology 28 nm 28 nm
Texture fill rate 23.83 22.7 billion/sec
Floating-point performance 762.6 gflops 544.5 gflops
Memory bus width 64 Bit 128bit
Memory clock speed 4000 MHz 1800 MHz
Memory bandwidth 40.1 GB/s
Shared memory - -
DirectX 12 (11_0) 12 API
Shader Model 5.1 5.1
OpenGL 4.5 4.5
OpenCL 1.2 1.1
Vulkan 1.1 1.1.126
CUDA + +
CUDA cores 384
Bus support PCI Express 3.0 PCI Express 2.0, PCI Express 3.0
HDMI +
HDCP +
Maximum VGA resolution Up to 2048x1536
3D Blu-Ray +
Bitcoin / BTC (SHA256) 102 Mh/s 19 Mh/s
Laptop size medium sized medium sized
Optimus + +
GPU Boost 2.0
GameWorks +
  Check Price Check Price