Radeon HD 4850 1GB vs Radeon HD 6870

Intro

Compare all that to the Radeon HD 6870, which features clock speeds of 900 MHz on the GPU, and 1050 MHz on the 1024 MB of GDDR5 memory. It features 1120 SPUs along with 56 TAUs and 32 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 1GB		110 Watts
Radeon HD 6870		151 Watts
	Difference: 41 Watts (37%)

Memory Bandwidth

The Radeon HD 6870 should in theory perform a lot faster than the Radeon HD 4850 1GB overall. (explain)

Radeon HD 6870		134400 MB/sec
Radeon HD 4850 1GB		63552 MB/sec
	Difference: 70848 (111%)

Texel Rate

The Radeon HD 6870 will be quite a bit (more or less 102%) faster with regards to texture filtering than the Radeon HD 4850 1GB. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon HD 4850 1GB		25000 Mtexels/sec
	Difference: 25400 (102%)

Pixel Rate

If using a high resolution is important to you, then the Radeon HD 6870 is superior to the Radeon HD 4850 1GB, by a large margin. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon HD 4850 1GB		10000 Mpixels/sec
	Difference: 18800 (188%)

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 maximum amount of data (measured in MB per second) that can be moved over the external memory interface in a second. It's worked out by multiplying the card's interface width by the speed of its memory. If it uses DDR RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This figure is calculated by multiplying the total amount of texture units 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 applied in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also called 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 memory bandwidth is, the lower the potential to get to the maximum fill rate.