Radeon HD 4670 1GB vs Radeon HD 6770

Intro

Compare those specs to the Radeon HD 6770, which uses a 40 nm design. AMD has clocked the core speed at 900 MHz. The GDDR5 RAM is set to run at a speed of 1050 MHz on this particular card. It features 800 SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4670 1GB		70 Watts
Radeon HD 6770		108 Watts
	Difference: 38 Watts (54%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 6770 should perform much faster than the Radeon HD 4670 1GB overall. (explain)

Radeon HD 6770		67200 MB/sec
Radeon HD 4670 1GB		35200 MB/sec
	Difference: 32000 (91%)

Texel Rate

The Radeon HD 6770 should be quite a bit (approximately 50%) better at anisotropic filtering than the Radeon HD 4670 1GB. (explain)

Radeon HD 6770		36000 Mtexels/sec
Radeon HD 4670 1GB		24000 Mtexels/sec
	Difference: 12000 (50%)

Pixel Rate

If running with a high screen resolution is important to you, then the Radeon HD 6770 is a better choice, by a large margin. (explain)

Radeon HD 6770		14400 Mpixels/sec
Radeon HD 4670 1GB		6000 Mpixels/sec
	Difference: 8400 (140%)

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 data (measured in megabytes per second) that can be transferred across the external memory interface in a second. It is calculated by multiplying the bus width by its memory clock speed. In the case of DDR type memory, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed per second. This figure is calculated by multiplying the total number of 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to its local memory per second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.