Radeon HD 4670 1GB vs Radeon HD 6870

Intro

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

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4670 1GB		70 Watts
Radeon HD 6870		151 Watts
	Difference: 81 Watts (116%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 6870 should be quite a bit faster than the Radeon HD 4670 1GB in general. (explain)

Radeon HD 6870		134400 MB/sec
Radeon HD 4670 1GB		35200 MB/sec
	Difference: 99200 (282%)

Texel Rate

The Radeon HD 6870 will be quite a bit (approximately 110%) more effective at AF than the Radeon HD 4670 1GB. (explain)

Radeon HD 6870		50400 Mtexels/sec
Radeon HD 4670 1GB		24000 Mtexels/sec
	Difference: 26400 (110%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 6870 is the winner, by a large margin. (explain)

Radeon HD 6870		28800 Mpixels/sec
Radeon HD 4670 1GB		6000 Mpixels/sec
	Difference: 22800 (380%)

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 largest amount of data (measured in MB per second) that can be transported over the external memory interface within a second. It's calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This is worked out by multiplying the total amount of texture units by the core speed of the chip. The better this number, the better the 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 that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.