Radeon HD 7870 vs Radeon R9 285

Intro

Compare all of that to the Radeon R9 285, which comes with core clock speeds of 918 MHz on the GPU, and 1375 MHz on the 2048 MB of GDDR5 memory. It features 1792 SPUs as well as 112 Texture Address Units and 32 Rasterization Operator Units.

Display Graphs

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Benchmarks

These are real-world performance benchmarks that were submitted by Hardware Compare users. The scores seen here are the average of all benchmarks submitted for each respective test and hardware.

3DMark Fire Strike Graphics Score

Radeon R9 285		8500 points
Radeon HD 7870		6230 points
	Difference: 2270 (36%)

Ethereum Mining Hash Rate

Radeon R9 285		18 Mh/s
Radeon HD 7870		16 Mh/s
	Difference: 2 (13%)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7870		175 Watts
Radeon R9 285		190 Watts
	Difference: 15 Watts (9%)

Memory Bandwidth

Theoretically speaking, the Radeon R9 285 should be 15% faster than the Radeon HD 7870 in general, because of its higher data rate. (explain)

Radeon R9 285		176000 MB/sec
Radeon HD 7870		153600 MB/sec
	Difference: 22400 (15%)

Texel Rate

The Radeon R9 285 should be much (more or less 29%) better at AF than the Radeon HD 7870. (explain)

Radeon R9 285		102816 Mtexels/sec
Radeon HD 7870		80000 Mtexels/sec
	Difference: 22816 (29%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 7870 is the winner, but not by far. (explain)

Radeon HD 7870		32000 Mpixels/sec
Radeon R9 285		29376 Mpixels/sec
	Difference: 2624 (9%)

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 (in units of megabytes per second) that can be transported over the external memory interface in one second. It's worked out by multiplying the interface width by its memory clock speed. If the card has DDR type RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This is worked out by multiplying the total number of texture units by the core clock 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 in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could 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 - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.