Radeon HD 6770 1GB vs Radeon HD 7870

Intro

Compare all of that to the Radeon HD 7870, which comes with GPU core speed of 1000 MHz, and 2048 MB of GDDR5 RAM set to run at 1200 MHz through a 256-bit bus. It also is comprised of 1280 Stream Processors, 80 TAUs, and 32 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6770 1GB		108 Watts
Radeon HD 7870		175 Watts
	Difference: 67 Watts (62%)

Memory Bandwidth

The Radeon HD 7870, in theory, should be much faster than the Radeon HD 6770 1GB overall. (explain)

Radeon HD 7870		153600 MB/sec
Radeon HD 6770 1GB		67200 MB/sec
	Difference: 86400 (129%)

Texel Rate

The Radeon HD 7870 is a lot (more or less 122%) better at texture filtering than the Radeon HD 6770 1GB. (explain)

Radeon HD 7870		80000 Mtexels/sec
Radeon HD 6770 1GB		36000 Mtexels/sec
	Difference: 44000 (122%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 7870 is the winner, by far. (explain)

Radeon HD 7870		32000 Mpixels/sec
Radeon HD 6770 1GB		14400 Mpixels/sec
	Difference: 17600 (122%)

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 (in units of megabytes per second) that can be transported across the external memory interface in a second. The number is worked out by multiplying the bus width by its memory speed. If the card has DDR RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed per 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 per second.

Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the max fill rate.