GeForce GTX 980M vs Radeon R9 M390X

Intro

Compare all that to the Radeon R9 M390X, which has a core clock frequency of 723 MHz and a GDDR5 memory frequency of 1250 MHz. It also uses a 256-bit memory bus, and makes use of a 28 nm design. It is made up of 2048 SPUs, 128 TAUs, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 980M		100 Watts
Radeon R9 M390X		125 Watts
	Difference: 25 Watts (25%)

Memory Bandwidth

In theory, the Radeon R9 M390X will be 25% faster than the GeForce GTX 980M overall, because of its greater bandwidth. (explain)

Radeon R9 M390X		160000 MB/sec
GeForce GTX 980M		128000 MB/sec
	Difference: 32000 (25%)

Texel Rate

The GeForce GTX 980M will be a little bit (more or less 8%) faster with regards to anisotropic filtering than the Radeon R9 M390X. (explain)

GeForce GTX 980M		99648 Mtexels/sec
Radeon R9 M390X		92544 Mtexels/sec
	Difference: 7104 (8%)

Pixel Rate

If running with a high screen resolution is important to you, then the GeForce GTX 980M is a better choice, by far. (explain)

GeForce GTX 980M		66432 Mpixels/sec
Radeon R9 M390X		23136 Mpixels/sec
	Difference: 43296 (187%)

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: Bandwidth is the max amount of information (measured in MB per second) that can be transferred across the external memory interface in one second. It's calculated by multiplying the bus width by the speed of its memory. If the card has DDR memory, the result should be multiplied by 2 once 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 texture map elements (texels) that can be processed in one second. This is worked out by multiplying the total number of texture units by the core clock speed of the chip. The higher 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 a second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.