Compare any two graphics cards:
Radeon HD 6670 (OEM) vs Radeon HD 6770 1GB
IntroThe Radeon HD 6670 (OEM) uses a 40 nm design. AMD has clocked the core frequency at 800 MHz. The GDDR5 memory runs at a speed of 1000 MHz on this particular model. It features 480 SPUs along with 24 Texture Address Units and 8 ROPs.
Compare all that to the Radeon HD 6770 1GB, which has GPU clock speed of 900 MHz, and 1024 MB of GDDR5 memory running at 1050 MHz through a 128-bit bus. It also features 800 SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the Radeon HD 6770 1GB will be 5% faster than the Radeon HD 6670 (OEM) overall, because of its greater bandwidth. (explain)
Texel RateThe Radeon HD 6770 1GB should be quite a bit (about 88%) faster with regards to texture filtering than the Radeon HD 6670 (OEM). (explain)
Pixel RateIf using a high resolution is important to you, then the Radeon HD 6770 1GB 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 information (in units of megabytes per second) that can be moved across the external memory interface within a second. It's worked out by multiplying the card's bus width by the speed of its memory. If it uses DDR memory, it must be multiplied by 2 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 texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total number of texture units by the core 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 processed per second.
Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly write to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.