Radeon HD 3650 512MB vs Radeon HD 6870

Intro

Compare all of that to the Radeon HD 6870, which comes with core speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 memory. It features 1120 SPUs as well as 56 TAUs and 32 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3650 512MB		78 Watts
Radeon HD 6870		151 Watts
	Difference: 73 Watts (94%)

Memory Bandwidth

As far as performance goes, the Radeon HD 6870 should in theory be quite a bit better than the Radeon HD 3650 512MB overall. (explain)

Radeon HD 6870		134400 MB/sec
Radeon HD 3650 512MB		25600 MB/sec
	Difference: 108800 (425%)

Texel Rate

The Radeon HD 6870 should be much (more or less 769%) better at texture filtering than the Radeon HD 3650 512MB. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon HD 3650 512MB		5800 Mtexels/sec
	Difference: 44600 (769%)

Pixel Rate

The Radeon HD 6870 should be quite a bit (about 893%) more effective at FSAA than the Radeon HD 3650 512MB, and also should be able to handle higher screen resolutions without slowing down too much. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon HD 3650 512MB		2900 Mpixels/sec
	Difference: 25900 (893%)

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 max amount of data (measured in megabytes per second) that can be transferred over the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory clock speed. In the case of DDR type 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 AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This number is calculated by multiplying the total amount of texture units of the card by the core 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 processed per second.

Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to the local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.