Compare any two graphics cards:
Radeon HD 6950 vs Radeon HD 7870
IntroThe Radeon HD 6950 features a core clock speed of 800 MHz and a GDDR5 memory frequency of 1250 MHz. It also features a 256-bit bus, and makes use of a 40 nm design. It is comprised of 1408 SPUs, 88 TAUs, and 32 ROPs.
Compare that to the Radeon HD 7870, which uses a 28 nm design. AMD has set the core frequency at 1000 MHz. The GDDR5 memory works at a frequency of 1200 MHz on this model. It features 1280 SPUs along with 80 Texture Address Units and 32 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the Radeon HD 6950 should perform just a bit faster than the Radeon HD 7870 overall. (explain)
Texel RateThe Radeon HD 7870 is a small bit (approximately 14%) more effective at anisotropic filtering than the Radeon HD 6950. (explain)
Pixel RateIf running with a high resolution is important to you, then the Radeon HD 7870 is a better choice, by a large margin. (explain)
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.
Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
Memory Bandwidth: Bandwidth is the largest amount of data (measured in megabytes per second) that can be transferred across the external memory interface in one second. It is calculated by multiplying the bus width by the speed of its memory. If it uses DDR type memory, it must be multiplied by 2 again. If it uses 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 high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This figure is calculated by multiplying the total amount of texture units of the card by the core speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.
Pixel Rate: Pixel rate is the most pixels the video card can possibly record to its 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 core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.