Radeon HD 7770 vs Radeon R7 250X 2GB

Intro

Compare all of that to the Radeon R7 250X 2GB, which comes with core clock speeds of 1000 MHz on the GPU, and 1125 MHz on the 2048 MB of GDDR5 RAM. It features 640 SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
Radeon R7 250X 2GB		95 Watts
	Difference: 15 Watts (19%)

Memory Bandwidth

Both cards have exactly the same memory bandwidth, so theoretically they should perform the same. (explain)

Texel Rate

Both cards have the exact same texel rate, so in theory they should perform equally good at at AF. (explain)

Pixel Rate

Both cards have exactly the same pixel rate, so in theory they should perform equally good at at anti-aliasing, and be capable of handling the same screen resolutions. (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.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the maximum amount of data (in units of MB per second) that can be transported past the external memory interface in a second. The number is calculated by multiplying the interface width by the speed of its memory. If it uses DDR memory, 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 texture map elements (texels) that are applied in one second. This number is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, the better the 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 the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the max fill rate.