Compare any two graphics cards:
GeForce 8800 GTS (G80) 640MB vs Radeon HD 4650 1GB
IntroThe GeForce 8800 GTS (G80) 640MB has core speeds of 513 MHz on the GPU, and 792 MHz on the 640 MB of GDDR3 RAM. It features 96 SPUs as well as 48 Texture Address Units and 20 Rasterization Operator Units.
Compare all that to the Radeon HD 4650 1GB, which comes with GPU core speed of 600 MHz, and 1024 MB of GDDR3 memory running at 700 MHz through a 128-bit bus. It also features 320(64x5) SPUs, 32 TAUs, and 8 Raster Operation Units.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
In theory, the GeForce 8800 GTS (G80) 640MB is 183% faster than the Radeon HD 4650 1GB in general, due to its higher bandwidth. (explain)
Texel RateThe GeForce 8800 GTS (G80) 640MB will be a lot (more or less 28%) more effective at AF than the Radeon HD 4650 1GB. (explain)
Pixel RateIf using high levels of AA is important to you, then the GeForce 8800 GTS (G80) 640MB is superior to the Radeon HD 4650 1GB, 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 max amount of information (counted in megabytes per second) that can be transferred over the external memory interface in one second. It is calculated by multiplying the interface width by its memory clock speed. In the case of DDR type RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster 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 are applied per second. This figure is calculated 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 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 write to its local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of 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 output rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.