GT 840M Specs
|Model||GT 840M (Maxwell I)|
|Core||GM108, 384 cores @ 1.03GHZ - 1.15GHZ|
|VRAM||2GB/4GB DDR3 @ 1GHZ (2GHZ eff.), 64-bit.|
|GFLOPS (w/Boost)||883 (FP32)|
|Memory bandwidth||14 GB/s|
The GT 840M is a low tier GPU based on the Maxwell I GM108 core and using GDDR5, released in 2014. It was a big upgrade from previous generation GT 740M which was based on the previous Kepler architecture. At its time, the 840M cost effectiveness was rather low due to being available in laptops priced at around $500-$600 the least. Compared to new low-tier GPUs like the Nvidia MX150 and the AMD Vega 8 iGPU inside the mobile Ryzen 2500U, it’s vastly outperformed while prices are the same, if the laptop is carefully picked.
The performance of the GT 840M before it, is enough for low-medium graphics gaming@768p/1080p, but some of the more demanding 3D games won’t run smoothly even at 768p. For example, Fornite at medium settings will run at around 35-40FPS. The newer Nvidia MX150 is at least 50% faster and often is twice as fast for gaming, so a GT 840M and even the 940M/X GDDR5 version competitiveness is low compared to a $450-$500 MX150 based laptop, and the GDDR5 version is the faster of them.
The GT 840M was incarnated into the 940M which was incarnated into the 940MX which incarnated into the MX130 which is still in use in 2018, but performance for DDR3 version are basically the same.
- GT 840M
- GT 940M
- GT 940MX GDDR5 (GM107)
At this point, it would be better to look for other GPUs, even for low priced machines. Laptop with the Nvidia MX150 GPU or the AMD 2500U CPU (with Vega 8 based iGPU) will be much preferable.