Compare any two graphics cards:

GeForce 820M vs GeForce 840M

Intro

The GeForce 820M has a clock speed of 719 MHz and a DDR3 memory frequency of 1000 MHz. It also makes use of a 64-bit memory bus, and makes use of a 28 nm design. It is comprised of 96 SPUs, 16 TAUs, and 4 Raster Operation Units.

Compare all that to the GeForce 840M, which features a clock speed of 1029 MHz and a DDR3 memory speed of 1000 MHz. It also features a 64-bit bus, and makes use of a 28 nm design. It features 384 SPUs, 24 Texture Address Units, and 8 Raster Operation Units.

Display Graphs

Hide Graphs

Benchmarks

These are real-world performance benchmarks that were submitted by Hardware Compare users. The scores seen here are the average of all benchmarks submitted for each respective test and hardware.

3DMark Fire Strike Graphics Score

GeForce 840M		1600 points
GeForce 820M		850 points
	Difference: 750 (88%)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 820M		15 Watts
GeForce 840M		30 Watts
	Difference: 15 Watts (100%)

Memory Bandwidth

Both cards have the exact same memory bandwidth, so theoretically they should perform the same. (explain)

Texel Rate

The GeForce 840M is a lot (approximately 115%) faster with regards to texture filtering than the GeForce 820M. (explain)

GeForce 840M		24696 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 13192 (115%)

Pixel Rate

If using high levels of AA is important to you, then the GeForce 840M is superior to the GeForce 820M, by far. (explain)

GeForce 840M		8232 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 5356 (186%)

Please note that the above 'benchmarks' are all just theoretical - the results were calculated based on the card's specifications, and real-world performance may (and probably will) vary at least a bit.

Price Comparison

Display Prices

Hide Prices

GeForce 820M

Amazon.com

Check prices at:

GeForce 840M

Amazon.com

Check prices at:

Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.

Specifications

Display Specifications

Hide Specifications

Model	GeForce 820M	GeForce 840M
Manufacturer	nVidia	nVidia
Year	February 2014	March 12 2014
Code Name	GF117	GM108
Memory	2048 MB	2048 MB
Core Speed	719 MHz	1029 MHz
Memory Speed	2000 MHz	2000 MHz
Power (Max TDP)	15 watts	30 watts
Bandwidth	16000 MB/sec	16000 MB/sec
Texel Rate	11504 Mtexels/sec	24696 Mtexels/sec
Pixel Rate	2876 Mpixels/sec	8232 Mpixels/sec
Unified Shaders	96	384
Texture Mapping Units	16	24
Render Output Units	4	8
Bus Type	DDR3	DDR3
Bus Width	64-bit	64-bit
Fab Process	28 nm	28 nm
Transistors	(Unknown) million	(Unknown) million
Bus	PCIe 2.0 x16	PCIe 3.0 x16
DirectX Version	DirectX 12	DirectX 12
OpenGL Version	OpenGL 4.5	OpenGL 4.5

Memory Bandwidth: Bandwidth is the maximum amount of data (measured in megabytes per second) that can be transferred past the external memory interface within a second. The number is worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This number is worked out by multiplying the total amount of texture units by the core speed of the chip. The better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly record to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.

Display Prices

Hide Prices