Radeon HD 4850 512MB vs Radeon HD 6950 2GB

Intro

Compare that to the Radeon HD 6950 2GB, which uses a 40 nm design. AMD has clocked the core speed at 800 MHz. The GDDR5 RAM works at a frequency of 1250 MHz on this particular model. It features 1408 SPUs along with 88 TAUs and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 512MB		110 Watts
Radeon HD 6950 2GB		200 Watts
	Difference: 90 Watts (82%)

Memory Bandwidth

The Radeon HD 6950 2GB, in theory, should be a lot faster than the Radeon HD 4850 512MB in general. (explain)

Radeon HD 6950 2GB		160000 MB/sec
Radeon HD 4850 512MB		63552 MB/sec
	Difference: 96448 (152%)

Texel Rate

The Radeon HD 6950 2GB is quite a bit (more or less 182%) more effective at AF than the Radeon HD 4850 512MB. (explain)

Radeon HD 6950 2GB		70400 Mtexels/sec
Radeon HD 4850 512MB		25000 Mtexels/sec
	Difference: 45400 (182%)

Pixel Rate

The Radeon HD 6950 2GB should be much (about 156%) more effective at full screen anti-aliasing than the Radeon HD 4850 512MB, and also able to handle higher screen resolutions more effectively. (explain)

Radeon HD 6950 2GB		25600 Mpixels/sec
Radeon HD 4850 512MB		10000 Mpixels/sec
	Difference: 15600 (156%)

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 max amount of data (counted in MB per second) that can be transported past the external memory interface in one second. It is worked out by multiplying the interface width by its memory clock speed. In the case of DDR RAM, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card can possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.