Radeon HD 3870 512MB vs Radeon HD 5570

Intro

Compare all of that to the Radeon HD 5570, which comes with a GPU core clock speed of 650 MHz, and 512 MB of DDR3 memory set to run at 900 MHz through a 128-bit bus. It also is comprised of 400(80x5) SPUs, 20 Texture Address Units, and 8 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 5570		43 Watts
Radeon HD 3870 512MB		106 Watts
	Difference: 63 Watts (147%)

Memory Bandwidth

As far as performance goes, the Radeon HD 3870 512MB should theoretically be quite a bit superior to the Radeon HD 5570 in general. (explain)

Radeon HD 3870 512MB		57600 MB/sec
Radeon HD 5570		28800 MB/sec
	Difference: 28800 (100%)

Texel Rate

The Radeon HD 5570 should be just a bit (approximately 5%) more effective at AF than the Radeon HD 3870 512MB. (explain)

Radeon HD 5570		13000 Mtexels/sec
Radeon HD 3870 512MB		12400 Mtexels/sec
	Difference: 600 (5%)

Pixel Rate

The Radeon HD 3870 512MB should be a lot (more or less 138%) more effective at anti-aliasing than the Radeon HD 5570, and should be capable of handling higher screen resolutions without slowing down too much. (explain)

Radeon HD 3870 512MB		12400 Mpixels/sec
Radeon HD 5570		5200 Mpixels/sec
	Difference: 7200 (138%)

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 information (in units of megabytes per second) that can be moved across the external memory interface in a second. It's worked out by multiplying the interface width by its memory clock speed. If it uses DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total amount of texture units by the core clock speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). 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 get to the maximum fill rate.