Radeon HD 5870 vs Radeon HD 7870 XT

Intro

Compare all of that to the Radeon HD 7870 XT, which makes use of a 28 nm design. AMD has clocked the core speed at 925 MHz. The GDDR5 memory is set to run at a speed of 1500 MHz on this specific model. It features 1536 SPUs as well as 96 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7870 XT		185 Watts
Radeon HD 5870		188 Watts
	Difference: 3 Watts (2%)

Memory Bandwidth

In theory, the Radeon HD 7870 XT will be 25% faster than the Radeon HD 5870 in general, because of its higher bandwidth. (explain)

Radeon HD 7870 XT		192000 MB/sec
Radeon HD 5870		153600 MB/sec
	Difference: 38400 (25%)

Texel Rate

The Radeon HD 7870 XT is quite a bit (about 31%) faster with regards to anisotropic filtering than the Radeon HD 5870. (explain)

Radeon HD 7870 XT		88800 Mtexels/sec
Radeon HD 5870		68000 Mtexels/sec
	Difference: 20800 (31%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 7870 XT is the winner, but only just. (explain)

Radeon HD 7870 XT		29600 Mpixels/sec
Radeon HD 5870		27200 Mpixels/sec
	Difference: 2400 (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 max amount of information (in units of megabytes per second) that can be transported past the external memory interface in a second. It is worked out by multiplying the bus width by its memory clock speed. In the case of DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is calculated by multiplying the total texture units of the card by the core speed of the chip. The better this number, the better the video 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 that the graphics chip can possibly record to the local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on quite a few 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.