Radeon HD 7870 vs Radeon R9 285

Intro

Compare those specifications to the Radeon R9 285, which has a core clock frequency of 918 MHz and a GDDR5 memory frequency of 1375 MHz. It also makes use of a 256-bit memory bus, and uses a 28 nm design. It is comprised of 1792 SPUs, 112 Texture Address Units, and 32 ROPs.

Display Graphs

Hide Graphs

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

The Radeon R9 285 should theoretically perform a small bit faster than the Radeon HD 7870 overall. (explain)

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

Texel Rate

The Radeon R9 285 is much (more or less 29%) more effective 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 using a high screen resolution is important to you, then the Radeon HD 7870 is a better choice, though only just barely. (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: Memory bandwidth is the maximum amount of data (counted in megabytes per second) that can be transferred over the external memory interface in one second. The number is worked out by multiplying the bus width by the speed of its memory. If it uses DDR type RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better 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 in one second. This figure is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The higher this number, the better the video 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 the video card could possibly write to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel 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 max fill rate.