GeForce GT 640 OEM Rebrand vs 840A
Primary details
GPU architecture, market segment, value for money and other general parameters compared.
| Place in the ranking | 779 | not rated |
| Place by popularity | not in top-100 | not in top-100 |
| Power efficiency | 6.28 | no data |
| Architecture | Maxwell (2014−2017) | Fermi 2.0 (2010−2014) |
| GPU code name | GM108 | GF116 |
| Market segment | Laptop | Desktop |
| Release date | 17 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 | 384 | 144 |
| Core clock speed | 1029 MHz | 720 MHz |
| Boost clock speed | 1124 MHz | no data |
| Number of transistors | no data | 1,170 million |
| Manufacturing process technology | 28 nm | 40 nm |
| Power consumption (TDP) | 33 Watt | 75 Watt |
| Texture fill rate | 17.98 | 17.28 |
| Floating-point processing power | 0.8632 TFLOPS | 0.4147 TFLOPS |
| ROPs | 8 | 24 |
| TMUs | 16 | 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).
| Interface | PCIe 3.0 x8 | PCIe 2.0 x16 |
| Length | no data | 145 mm |
| Width | no data | 1-slot |
| Supplementary power connectors | no data | None |
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 | DDR3 | DDR3 |
| Maximum RAM amount | 2 GB | 1536 MB |
| Memory bus width | 64 Bit | 192 Bit |
| Memory clock speed | 1001 MHz | 800 MHz |
| Memory bandwidth | 16.02 GB/s | 38.4 GB/s |
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 |
| HDMI | - | + |
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 | 4.6 | 4.6 |
| OpenCL | 1.2 | 1.1 |
| Vulkan | 1.1.126 | N/A |
| CUDA | 5.0 | 2.1 |
Pros & cons summary
| Recency | 17 March 2014 | 24 April 2012 |
| Maximum RAM amount | 2 GB | 1536 MB |
| Chip lithography | 28 nm | 40 nm |
| Power consumption (TDP) | 33 Watt | 75 Watt |
GeForce 840A has an age advantage of 1 year, a 33.3% higher maximum VRAM amount, a 42.9% more advanced lithography process, and 127.3% lower power consumption.
We couldn't decide between GeForce 840A and GeForce GT 640 OEM Rebrand. We've got no test results to judge.
Be aware that GeForce 840A is a notebook card while GeForce GT 640 OEM Rebrand is a desktop one.
Should you still have questions concerning choice between the reviewed GPUs, ask them in Comments section, and we shall answer.
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