Radeon HD 4870 1GB vs Radeon HD 6970

Intro

Compare that to the Radeon HD 6970, which has clock speeds of 880 MHz on the GPU, and 1375 MHz on the 2048 MB of GDDR5 RAM. It features 1536 SPUs as well as 96 Texture Address Units and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4870 1GB		150 Watts
Radeon HD 6970		250 Watts
	Difference: 100 Watts (67%)

Memory Bandwidth

As far as performance goes, the Radeon HD 6970 should in theory be quite a bit superior to the Radeon HD 4870 1GB in general. (explain)

Radeon HD 6970		176000 MB/sec
Radeon HD 4870 1GB		115200 MB/sec
	Difference: 60800 (53%)

Texel Rate

The Radeon HD 6970 is a lot (approximately 182%) better at AF than the Radeon HD 4870 1GB. (explain)

Radeon HD 6970		84480 Mtexels/sec
Radeon HD 4870 1GB		30000 Mtexels/sec
	Difference: 54480 (182%)

Pixel Rate

The Radeon HD 6970 should be quite a bit (more or less 135%) better at anti-aliasing than the Radeon HD 4870 1GB, and also should be capable of handling higher screen resolutions without slowing down too much. (explain)

Radeon HD 6970		28160 Mpixels/sec
Radeon HD 4870 1GB		12000 Mpixels/sec
	Difference: 16160 (135%)

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 (in units of megabytes per second) that can be transported over the external memory interface within a second. It's calculated by multiplying the interface width by the speed of its memory. If it uses DDR RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This number is worked out by multiplying the total texture units by the core 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 in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the clock speed of the card. 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 output rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.