Radeon HD 4670 512MB vs Radeon HD 6990

Intro

Compare all that to the Radeon HD 6990, which comes with a core clock frequency of 830 MHz and a GDDR5 memory speed of 1250 MHz. It also features a 256-bit memory bus, and makes use of a 40 nm design. It is comprised of 1536 SPUs, 96 TAUs, and 32 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4670 512MB		70 Watts
Radeon HD 6990		375 Watts
	Difference: 305 Watts (436%)

Memory Bandwidth

In theory, the Radeon HD 6990 should be a lot faster than the Radeon HD 4670 512MB overall. (explain)

Radeon HD 6990		320000 MB/sec
Radeon HD 4670 512MB		32000 MB/sec
	Difference: 288000 (900%)

Texel Rate

The Radeon HD 6990 will be a lot (about 564%) faster with regards to AF than the Radeon HD 4670 512MB. (explain)

Radeon HD 6990		159360 Mtexels/sec
Radeon HD 4670 512MB		24000 Mtexels/sec
	Difference: 135360 (564%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon HD 6990 is the winner, and very much so. (explain)

Radeon HD 6990		53120 Mpixels/sec
Radeon HD 4670 512MB		6000 Mpixels/sec
	Difference: 47120 (785%)

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 maximum amount of information (in units of megabytes per second) that can be transported across the external memory interface within a second. It is worked out by multiplying the bus width by its memory clock speed. If the card has 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, 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 calculated by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the graphics card will be at 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 record to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel output rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.