Radeon HD 4850 X2 512MB vs Radeon HD 7950 3GB

Intro

Compare those specifications to the Radeon HD 7950 3GB, which comes with GPU clock speed of 800 MHz, and 3072 MB of GDDR5 memory running at 1250 MHz through a 384-bit bus. It also is comprised of 1792 SPUs, 112 TAUs, and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7950 3GB		200 Watts
Radeon HD 4850 X2 512MB		250 Watts
	Difference: 50 Watts (25%)

Memory Bandwidth

Theoretically, the Radeon HD 7950 3GB should perform quite a bit faster than the Radeon HD 4850 X2 512MB in general. (explain)

Radeon HD 7950 3GB		240000 MB/sec
Radeon HD 4850 X2 512MB		127104 MB/sec
	Difference: 112896 (89%)

Texel Rate

The Radeon HD 7950 3GB should be much (about 79%) more effective at anisotropic filtering than the Radeon HD 4850 X2 512MB. (explain)

Radeon HD 7950 3GB		89600 Mtexels/sec
Radeon HD 4850 X2 512MB		50000 Mtexels/sec
	Difference: 39600 (79%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 7950 3GB is a better choice, and very much so. (explain)

Radeon HD 7950 3GB		25600 Mpixels/sec
Radeon HD 4850 X2 512MB		20000 Mpixels/sec
	Difference: 5600 (28%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the max amount of information (measured in MB per second) that can be moved over the external memory interface in one second. It is worked out by multiplying the interface width by its memory speed. If the card has DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the 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 texture map elements (texels) that are processed in one second. This is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The higher 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 most pixels that the graphics card could possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate is also dependant on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the max fill rate.