GeForce 825M vs GeForce GTX 980M

Intro

Compare all of that to the GeForce GTX 980M, which comes with a core clock frequency of 1038 MHz and a GDDR5 memory speed of 1000 MHz. It also makes use of a 256-bit bus, and uses a 28 nm design. It is made up of 1536 SPUs, 96 Texture Address Units, and 64 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 825M		33 Watts
GeForce GTX 980M		100 Watts
	Difference: 67 Watts (203%)

Memory Bandwidth

Theoretically speaking, the GeForce GTX 980M will be 789% quicker than the GeForce 825M overall, due to its higher bandwidth. (explain)

GeForce GTX 980M		128000 MB/sec
GeForce 825M		14400 MB/sec
	Difference: 113600 (789%)

Texel Rate

The GeForce GTX 980M is quite a bit (about 633%) more effective at texture filtering than the GeForce 825M. (explain)

GeForce GTX 980M		99648 Mtexels/sec
GeForce 825M		13600 Mtexels/sec
	Difference: 86048 (633%)

Pixel Rate

The GeForce GTX 980M is quite a bit (approximately 877%) more effective at FSAA than the GeForce 825M, and also will be capable of handling higher screen resolutions without slowing down too much. (explain)

GeForce GTX 980M		66432 Mpixels/sec
GeForce 825M		6800 Mpixels/sec
	Difference: 59632 (877%)

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

Specifications

Memory Bandwidth: Memory bandwidth is the max amount of information (counted in megabytes per second) that can be transferred across the external memory interface within a second. The number is worked out by multiplying the card's interface width by the speed of its memory. If the card has DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.