Radeon HD 4870 1GB 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 is set to run at a frequency of 1250 MHz on this card. It features 1408 SPUs along with 88 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 6950		200 Watts
	Difference: 50 Watts (33%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 6950 should be 39% faster than the Radeon HD 4870 1GB in general, due to its higher bandwidth. (explain)

Radeon HD 6950		160000 MB/sec
Radeon HD 4870 1GB		115200 MB/sec
	Difference: 44800 (39%)

Texel Rate

The Radeon HD 6950 will be much (approximately 135%) faster with regards to texture filtering than the Radeon HD 4870 1GB. (explain)

Radeon HD 6950		70400 Mtexels/sec
Radeon HD 4870 1GB		30000 Mtexels/sec
	Difference: 40400 (135%)

Pixel Rate

The Radeon HD 6950 will be quite a bit (about 113%) better at anti-aliasing than the Radeon HD 4870 1GB, and should be able to handle higher screen resolutions more effectively. (explain)

Radeon HD 6950		25600 Mpixels/sec
Radeon HD 4870 1GB		12000 Mpixels/sec
	Difference: 13600 (113%)

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: Bandwidth is the largest amount of information (measured in MB per second) that can be transported over the external memory interface in a second. The number is calculated by multiplying the interface width by the speed of its memory. In the case of DDR type memory, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster 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 amount of texture map elements (texels) that can be processed in one second. This figure is worked out by multiplying the total amount of texture units of the card by the core speed of the chip. The higher this number, the better the 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 amount of pixels the video card can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Render Output Units 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 also depends on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.