Radeon HD 5870 vs Radeon HD 7850

Intro

Compare those specifications to the Radeon HD 7850, which has clock speeds of 860 MHz on the GPU, and 1200 MHz on the 2048 MB of GDDR5 memory. It features 1024 SPUs along with 64 TAUs and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7850		130 Watts
Radeon HD 5870		188 Watts
	Difference: 58 Watts (45%)

Memory Bandwidth

Both cards have exactly the same bandwidth, so in theory they should perform the same. (explain)

Texel Rate

The Radeon HD 5870 is quite a bit (approximately 24%) better at texture filtering than the Radeon HD 7850. (explain)

Radeon HD 5870		68000 Mtexels/sec
Radeon HD 7850		55040 Mtexels/sec
	Difference: 12960 (24%)

Pixel Rate

The Radeon HD 7850 should be just a bit (approximately 1%) faster with regards to anti-aliasing than the Radeon HD 5870, and also should be capable of handling higher resolutions while still performing well. (explain)

Radeon HD 7850		27520 Mpixels/sec
Radeon HD 5870		27200 Mpixels/sec
	Difference: 320 (1%)

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 (counted in megabytes per second) that can be transported past the external memory interface in one second. It is worked out by multiplying the interface width by its memory speed. If the card has DDR RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster 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 texture map elements (texels) that can be applied in one second. This number is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. 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 lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.