Radeon HD 4830 1GB vs Radeon HD 6870

Intro

Compare those specs to the Radeon HD 6870, which uses a 40 nm design. AMD has clocked the core speed at 900 MHz. The GDDR5 memory is set to run at a speed of 1050 MHz on this specific card. It features 1120 SPUs along with 56 TAUs and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4830 1GB		95 Watts
Radeon HD 6870		151 Watts
	Difference: 56 Watts (59%)

Memory Bandwidth

The Radeon HD 6870 should in theory be quite a bit faster than the Radeon HD 4830 1GB overall. (explain)

Radeon HD 6870		134400 MB/sec
Radeon HD 4830 1GB		57600 MB/sec
	Difference: 76800 (133%)

Texel Rate

The Radeon HD 6870 should be a lot (more or less 174%) more effective at anisotropic filtering than the Radeon HD 4830 1GB. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon HD 4830 1GB		18400 Mtexels/sec
	Difference: 32000 (174%)

Pixel Rate

The Radeon HD 6870 is much (more or less 213%) more effective at anti-aliasing than the Radeon HD 4830 1GB, and able to handle higher screen resolutions better. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon HD 4830 1GB		9200 Mpixels/sec
	Difference: 19600 (213%)

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 (counted in megabytes per second) that can be transported over the external memory interface in one second. It's worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the card's 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 texture map elements (texels) that are processed per second. This is worked out by multiplying the total amount of texture units by the core speed of the chip. The higher the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel 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 max fill rate.