Compare any two graphics cards:
GeForce GT 240 GDDR5 vs Radeon HD 4670 512MB
IntroThe GeForce GT 240 GDDR5 features a core clock frequency of 550 MHz and a GDDR5 memory frequency of 850 MHz. It also makes use of a 128-bit bus, and uses a 40 nm design. It is made up of 96 SPUs, 32 TAUs, and 8 Raster Operation Units.
Compare all that to the Radeon HD 4670 512MB, which has core speeds of 750 MHz on the GPU, and 1000 MHz on the 512 MB of GDDR4/GDDR3/DDR3/DDR2 RAM. It features 320(64x5) SPUs along with 32 TAUs and 8 Rasterization Operator Units.
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
In theory, the GeForce GT 240 GDDR5 is 70% quicker than the Radeon HD 4670 512MB overall, because of its higher data rate. (explain)
Texel RateThe Radeon HD 4670 512MB will be a lot (about 36%) faster with regards to AF than the GeForce GT 240 GDDR5. (explain)
Pixel RateThe Radeon HD 4670 512MB will be quite a bit (about 36%) better at FSAA than the GeForce GT 240 GDDR5, and will be capable of handling 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 largest amount of information (in units of MB per second) that can be transported past the external memory interface in one second. The number is worked out by multiplying the bus width by its memory clock speed. If the card has DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the faster 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 amount of texture map elements (texels) that can be applied per second. This is worked out by multiplying the total texture units by the core speed of the chip. The better this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.