Compare any two graphics cards:
GeForce GTX 965M vs Radeon HD 3870 512MB
IntroThe GeForce GTX 965M has a GPU core speed of 944 MHz, and the 2048 MB of GDDR5 memory is set to run at 1000 MHz through a 128-bit bus. It also is comprised of 1024 SPUs, 64 TAUs, and 32 ROPs.
Compare those specifications to the Radeon HD 3870 512MB, which uses a 55 nm design. AMD has clocked the core frequency at 775 MHz. The GDDR3 RAM is set to run at a frequency of 900 MHz on this particular model. It features 320(64x5) SPUs as well as 16 TAUs and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
Theoretically speaking, the GeForce GTX 965M should perform a bit faster than the Radeon HD 3870 512MB in general. (explain)
Texel RateThe GeForce GTX 965M is a lot (more or less 387%) better at anisotropic filtering than the Radeon HD 3870 512MB. (explain)
Pixel RateThe GeForce GTX 965M should be quite a bit (about 144%) faster with regards to AA than the Radeon HD 3870 512MB, and also should be able to handle higher resolutions while still performing well. (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 maximum amount of data (in units of MB per second) that can be transferred past the external memory interface within a second. The number is worked out by multiplying the card's bus width by its memory speed. In the case of DDR type memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This number is worked out by multiplying the total texture units by the core clock speed of the chip. The higher the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.
Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly record to its local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of Render Output Units 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 rate also depends on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.