Radeon HD 3870 512MB vs Radeon HD 6750 1GB

Intro

Compare all of that to the Radeon HD 6750 1GB, which features core clock speeds of 725 MHz on the GPU, and 1000 MHz on the 1024 MB of GDDR5 memory. It features 720 SPUs as well as 36 TAUs and 16 Rasterization Operator Units.

(No game benchmarks for this combination yet.)

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

Performance-wise, the Radeon HD 6750 1GB should in theory be a bit superior to the Radeon HD 3870 512MB in general. (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 is a lot (about 110%) more effective at AF 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

The Radeon HD 3870 512MB will be just a bit (about 7%) better at FSAA than the Radeon HD 6750 1GB, and also able to handle higher resolutions without losing too much performance. (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 largest amount of data (counted in megabytes per second) that can be transported over the external memory interface in one second. It's calculated by multiplying the interface width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the 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 can be applied per second. This is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The better this number, the better the video 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 amount of pixels that the graphics chip can possibly record to its local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.