Radeon HD 3870 512MB vs Radeon HD 6750 1GB

Intro

Compare that to the Radeon HD 6750 1GB, which has GPU core speed of 725 MHz, and 1024 MB of GDDR5 memory set to run at 1000 MHz through a 128-bit bus. It also is made up of 720 Stream Processors, 36 TAUs, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6750 1GB		86 Watts
Radeon HD 3870 512MB		106 Watts
	Difference: 20 Watts (23%)

Memory Bandwidth

As far as performance goes, the Radeon HD 6750 1GB should in theory be just a bit better than the Radeon HD 3870 512MB overall. (explain)

Radeon HD 6750 1GB		64000 MB/sec
Radeon HD 3870 512MB		57600 MB/sec
	Difference: 6400 (11%)

Texel Rate

The Radeon HD 6750 1GB should be much (approximately 110%) faster with regards to texture filtering than the Radeon HD 3870 512MB. (explain)

Radeon HD 6750 1GB		26100 Mtexels/sec
Radeon HD 3870 512MB		12400 Mtexels/sec
	Difference: 13700 (110%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 3870 512MB is a better choice, not by a very large margin though. (explain)

Radeon HD 3870 512MB		12400 Mpixels/sec
Radeon HD 6750 1GB		11600 Mpixels/sec
	Difference: 800 (7%)

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 maximum amount of data (measured in megabytes per second) that can be transferred across the external memory interface in one second. The number is worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR type memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better 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 number of texture units of the card by the core 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 per second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.