GeForce GTX 950 vs Radeon HD 4890 2GB

Intro

Compare those specifications to the Radeon HD 4890 2GB, which uses a 55 nm design. AMD has set the core speed at 1000 MHz. The GDDR5 memory runs at a speed of 975 MHz on this particular model. It features 800(160x5) SPUs as well as 40 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 950		90 Watts
Radeon HD 4890 2GB		190 Watts
	Difference: 100 Watts (111%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 4890 2GB is 18% faster than the GeForce GTX 950 overall, because of its greater bandwidth. (explain)

Radeon HD 4890 2GB		124800 MB/sec
GeForce GTX 950		105728 MB/sec
	Difference: 19072 (18%)

Texel Rate

The GeForce GTX 950 is a lot (about 23%) better at anisotropic filtering than the Radeon HD 4890 2GB. (explain)

GeForce GTX 950		49152 Mtexels/sec
Radeon HD 4890 2GB		40000 Mtexels/sec
	Difference: 9152 (23%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the GeForce GTX 950 is a better choice, and very much so. (explain)

GeForce GTX 950		32768 Mpixels/sec
Radeon HD 4890 2GB		16000 Mpixels/sec
	Difference: 16768 (105%)

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 information (counted in megabytes per second) that can be transferred over the external memory interface within a second. It's worked out by multiplying the card's interface width by its memory speed. If it uses DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This is worked out by multiplying the total number of 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 most pixels the video card could possibly write to its local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called 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, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.