GeForce GTX 980M vs Radeon HD 4890 2GB

Intro

Compare all of that to the Radeon HD 4890 2GB, which comes with a core clock frequency of 1000 MHz and a GDDR5 memory frequency of 975 MHz. It also makes use of a 256-bit memory bus, and uses a 55 nm design. It is comprised of 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 980M		100 Watts
Radeon HD 4890 2GB		190 Watts
	Difference: 90 Watts (90%)

Memory Bandwidth

As far as performance goes, the GeForce GTX 980M should theoretically be a little bit superior to the Radeon HD 4890 2GB in general. (explain)

GeForce GTX 980M		128000 MB/sec
Radeon HD 4890 2GB		124800 MB/sec
	Difference: 3200 (3%)

Texel Rate

The GeForce GTX 980M will be a lot (about 149%) more effective at anisotropic filtering than the Radeon HD 4890 2GB. (explain)

GeForce GTX 980M		99648 Mtexels/sec
Radeon HD 4890 2GB		40000 Mtexels/sec
	Difference: 59648 (149%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the GeForce GTX 980M is a better choice, and very much so. (explain)

GeForce GTX 980M		66432 Mpixels/sec
Radeon HD 4890 2GB		16000 Mpixels/sec
	Difference: 50432 (315%)

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: Memory bandwidth is the largest amount of information (measured in megabytes per second) that can be transferred across the external memory interface in one second. The number is calculated by multiplying the bus width by the speed of its memory. If the card has DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, 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 is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the maximum fill rate.