Radeon HD 4550 512MB vs Radeon HD 6950

Intro

Compare those specs to the Radeon HD 6950, which makes use of a 40 nm design. AMD has set the core speed at 800 MHz. The GDDR5 memory works at a frequency of 1250 MHz on this particular model. It features 1408 SPUs along with 88 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 4550 512MB		25 Watts
Radeon HD 6950		200 Watts
	Difference: 175 Watts (700%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 6950 is 1150% quicker than the Radeon HD 4550 512MB overall, because of its greater bandwidth. (explain)

Radeon HD 6950		160000 MB/sec
Radeon HD 4550 512MB		12800 MB/sec
	Difference: 147200 (1150%)

Texel Rate

The Radeon HD 6950 is a lot (about 1367%) better at anisotropic filtering than the Radeon HD 4550 512MB. (explain)

Radeon HD 6950		70400 Mtexels/sec
Radeon HD 4550 512MB		4800 Mtexels/sec
	Difference: 65600 (1367%)

Pixel Rate

The Radeon HD 6950 will be quite a bit (about 967%) more effective at full screen anti-aliasing than the Radeon HD 4550 512MB, and also will be capable of handling higher screen resolutions more effectively. (explain)

Radeon HD 6950		25600 Mpixels/sec
Radeon HD 4550 512MB		2400 Mpixels/sec
	Difference: 23200 (967%)

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 data (counted in megabytes per second) that can be moved over the external memory interface within a second. It's calculated by multiplying the bus width by its memory speed. In the case of DDR type memory, the result should be multiplied by 2 once 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 AA, High Dynamic Range and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.