GeForce GTX 870M vs Radeon R9 M380

Intro

Compare those specs to the Radeon R9 M380, which has a clock speed of 1000 MHz and a GDDR5 memory speed of 1500 MHz. It also uses a 128-bit bus, and makes use of a 28 nm design. It is made up of 640 SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

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

Texel Rate

The GeForce GTX 870M is a lot (more or less 163%) better at anisotropic filtering than the Radeon R9 M380. (explain)

GeForce GTX 870M		105392 Mtexels/sec
Radeon R9 M380		40000 Mtexels/sec
	Difference: 65392 (163%)

Pixel Rate

If using a high resolution is important to you, then the GeForce GTX 870M is a better choice, and very much so. (explain)

GeForce GTX 870M		22584 Mpixels/sec
Radeon R9 M380		16000 Mpixels/sec
	Difference: 6584 (41%)

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 largest amount of information (counted in megabytes per second) that can be transferred across the external memory interface within a second. It's calculated by multiplying the card's bus width by its memory clock speed. In the case of DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels the video card could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.