GeForce GTX 870M vs Radeon R9 M385X

Intro

Compare all of that to the Radeon R9 M385X, which features a GPU core clock speed of 1100 MHz, and 4096 MB of GDDR5 RAM running at 1500 MHz through a 128-bit bus. It also features 896 Stream Processors, 56 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

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

Texel Rate

The GeForce GTX 870M will be a lot (about 71%) better at AF than the Radeon R9 M385X. (explain)

GeForce GTX 870M		105392 Mtexels/sec
Radeon R9 M385X		61600 Mtexels/sec
	Difference: 43792 (71%)

Pixel Rate

The GeForce GTX 870M should be a lot (more or less 28%) better at AA than the Radeon R9 M385X, and also able to handle higher screen resolutions without losing too much performance. (explain)

GeForce GTX 870M		22584 Mpixels/sec
Radeon R9 M385X		17600 Mpixels/sec
	Difference: 4984 (28%)

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 data (in units of MB per second) that can be transferred past the external memory interface in one second. It is worked out by multiplying the bus width by the speed of its memory. If it uses DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster 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 are processed per second. This figure is calculated 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 texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

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