Radeon R9 390X 8G vs Radeon R9 M385X

Intro

Compare that to the Radeon R9 M385X, which comes with core speeds of 1100 MHz on the GPU, and 1500 MHz on the 4096 MB of GDDR5 RAM. It features 896 SPUs as well as 56 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Theoretically, the Radeon R9 390X 8G should be quite a bit faster than the Radeon R9 M385X in general. (explain)

Radeon R9 390X 8G		384000 MB/sec
Radeon R9 M385X		96000 MB/sec
	Difference: 288000 (300%)

Texel Rate

The Radeon R9 390X 8G should be a lot (about 200%) more effective at anisotropic filtering than the Radeon R9 M385X. (explain)

Radeon R9 390X 8G		184800 Mtexels/sec
Radeon R9 M385X		61600 Mtexels/sec
	Difference: 123200 (200%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon R9 390X 8G is a better choice, by a large margin. (explain)

Radeon R9 390X 8G		67200 Mpixels/sec
Radeon R9 M385X		17600 Mpixels/sec
	Difference: 49600 (282%)

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 data (measured in MB per second) that can be moved across the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range 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 is worked out by multiplying the total texture units of the card by the core clock speed of the chip. The higher the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

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