Radeon HD 3870 512MB vs Radeon HD 6870

Intro

Compare those specifications to the Radeon HD 6870, which uses a 40 nm design. AMD has clocked the core frequency at 900 MHz. The GDDR5 memory runs at a speed of 1050 MHz on this particular card. It features 1120 SPUs as well as 56 Texture Address Units and 32 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3870 512MB		106 Watts
Radeon HD 6870		151 Watts
	Difference: 45 Watts (42%)

Memory Bandwidth

Performance-wise, the Radeon HD 6870 should theoretically be much better than the Radeon HD 3870 512MB overall. (explain)

Radeon HD 6870		134400 MB/sec
Radeon HD 3870 512MB		57600 MB/sec
	Difference: 76800 (133%)

Texel Rate

The Radeon HD 6870 should be a lot (approximately 306%) faster with regards to texture filtering than the Radeon HD 3870 512MB. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon HD 3870 512MB		12400 Mtexels/sec
	Difference: 38000 (306%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 6870 is superior to the Radeon HD 3870 512MB, and very much so. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon HD 3870 512MB		12400 Mpixels/sec
	Difference: 16400 (132%)

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

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total amount of texture units of the card by the core clock 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 in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.