Radeon HD 4890 2GB vs Radeon R7 250X

Intro

Compare all that to the Radeon R7 250X, which features core clock speeds of 1000 MHz on the GPU, and 1125 MHz on the 1024 MB of GDDR5 memory. It features 640 SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R7 250X		95 Watts
Radeon HD 4890 2GB		190 Watts
	Difference: 95 Watts (100%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 4890 2GB should perform quite a bit faster than the Radeon R7 250X overall. (explain)

Radeon HD 4890 2GB		124800 MB/sec
Radeon R7 250X		72000 MB/sec
	Difference: 52800 (73%)

Texel Rate

Both cards have the exact same texel rate, so theoretically they should perform equally good at at anisotropic filtering. (explain)

Pixel Rate

Both cards have exactly the same pixel fill rate, so theoretically they should be equally good at at FSAA, 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 max amount of data (measured in MB per second) that can be transferred over the external memory interface in one second. The number is calculated by multiplying the card's bus width by its memory clock speed. If the card has DDR type 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, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied per second. This is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum number of pixels the video card can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.