Radeon HD 7870 XT vs Radeon R9 M385X

Intro

Compare those specifications to the Radeon R9 M385X, which uses a 28 nm design. AMD has set the core speed at 1100 MHz. The GDDR5 RAM runs at a speed of 1500 MHz on this particular card. 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

The Radeon HD 7870 XT, in theory, should be much faster than the Radeon R9 M385X in general. (explain)

Radeon HD 7870 XT		192000 MB/sec
Radeon R9 M385X		96000 MB/sec
	Difference: 96000 (100%)

Texel Rate

The Radeon HD 7870 XT should be a lot (about 44%) faster with regards to texture filtering than the Radeon R9 M385X. (explain)

Radeon HD 7870 XT		88800 Mtexels/sec
Radeon R9 M385X		61600 Mtexels/sec
	Difference: 27200 (44%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 7870 XT is a better choice, and very much so. (explain)

Radeon HD 7870 XT		29600 Mpixels/sec
Radeon R9 M385X		17600 Mpixels/sec
	Difference: 12000 (68%)

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 megabytes per second) that can be moved over the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory clock speed. In the case of DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This number is calculated by multiplying the total number of texture units by the core speed of the chip. The better this number, the better the video 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 maximum number of pixels that the graphics chip can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.