Radeon HD 4890 2GB vs Radeon R9 M380

Intro

Compare those specifications to the Radeon R9 M380, which comes with clock speeds of 1000 MHz on the GPU, and 1500 MHz on the 4096 MB of GDDR5 memory. It features 640 SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Memory Bandwidth

As far as performance goes, the Radeon HD 4890 2GB should theoretically be much better than the Radeon R9 M380 in general. (explain)

Radeon HD 4890 2GB		124800 MB/sec
Radeon R9 M380		96000 MB/sec
	Difference: 28800 (30%)

Texel Rate

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

Pixel Rate

Both cards have the exact 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 largest amount of data (counted in megabytes per second) that can be transported past 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 type RAM, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This 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 card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly write to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate also depends on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.