Compare any two graphics cards:
Radeon HD 4650 1GB vs Radeon HD 7750
IntroThe Radeon HD 4650 1GB uses a 55 nm design. AMD has clocked the core speed at 600 MHz. The GDDR3 RAM runs at a speed of 700 MHz on this particular card. It features 320(64x5) SPUs along with 32 Texture Address Units and 8 ROPs.
Compare those specifications to the Radeon HD 7750, which has GPU core speed of 800 MHz, and 1024 MB of GDDR5 memory running at 1125 MHz through a 128-bit bus. It also is comprised of 512 SPUs, 32 Texture Address Units, and 16 ROPs.
(No game benchmarks for this combination yet.)
Power Usage and Theoretical BenchmarksBoth cards have the same power consumption.
Theoretically speaking, the Radeon HD 7750 will be 221% quicker than the Radeon HD 4650 1GB overall, because of its higher bandwidth. (explain)
Texel RateThe Radeon HD 7750 will be quite a bit (more or less 33%) more effective at anisotropic filtering than the Radeon HD 4650 1GB. (explain)
Pixel RateIf using a high screen resolution is important to you, then the Radeon HD 7750 is a better choice, by far. (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 transferred over the external memory interface within a second. It's calculated by multiplying the bus width by the speed of its memory. If it uses DDR RAM, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total number of texture units of the card by the core 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 in one second.
Pixel Rate: Pixel rate is the maximum number of pixels the video card could possibly write to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.