GeForce GTX 870M vs Radeon R9 M380

Intro

Compare all of that to the Radeon R9 M380, which comes with clock speeds of 1000 MHz on the GPU, and 1500 MHz on the 4096 MB of GDDR5 memory. It features 640 SPUs as well as 40 TAUs and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

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

Texel Rate

The GeForce GTX 870M is quite a bit (more or less 163%) better at texture 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 screen 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: Memory bandwidth is the maximum amount of data (measured in megabytes per second) that can be transferred across the external memory interface in one second. It's worked out by multiplying the card's bus width by its memory speed. If it uses DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the clock 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 rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.