Radeon HD 4890 2GB vs Radeon HD 5870

Intro

Compare all that to the Radeon HD 5870, which uses a 40 nm design. AMD has set the core speed at 850 MHz. The GDDR5 RAM works at a frequency of 1200 MHz on this particular model. It features 1600(320x5) SPUs along with 80 Texture Address Units and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 5870		188 Watts
Radeon HD 4890 2GB		190 Watts
	Difference: 2 Watts (1%)

Memory Bandwidth

The Radeon HD 5870, in theory, should perform much faster than the Radeon HD 4890 2GB in general. (explain)

Radeon HD 5870		153600 MB/sec
Radeon HD 4890 2GB		124800 MB/sec
	Difference: 28800 (23%)

Texel Rate

The Radeon HD 5870 will be quite a bit (approximately 70%) faster with regards to AF than the Radeon HD 4890 2GB. (explain)

Radeon HD 5870		68000 Mtexels/sec
Radeon HD 4890 2GB		40000 Mtexels/sec
	Difference: 28000 (70%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 5870 is superior to the Radeon HD 4890 2GB, and very much so. (explain)

Radeon HD 5870		27200 Mpixels/sec
Radeon HD 4890 2GB		16000 Mpixels/sec
	Difference: 11200 (70%)

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: Memory bandwidth is the max amount of information (measured in MB per second) that can be moved across the external memory interface in one second. The number is worked out by multiplying the interface width by its memory speed. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This is calculated by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the max fill rate.