GeForce GTX 850M vs Radeon HD 4890 1GB

Intro

Compare those specs to the Radeon HD 4890 1GB, which features a 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 features 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 850M		40 Watts
Radeon HD 4890 1GB		190 Watts
	Difference: 150 Watts (375%)

Memory Bandwidth

Theoretically, the Radeon HD 4890 1GB should be a lot faster than the GeForce GTX 850M overall. (explain)

Radeon HD 4890 1GB		124800 MB/sec
GeForce GTX 850M		32000 MB/sec
	Difference: 92800 (290%)

Texel Rate

The Radeon HD 4890 1GB is a small bit (approximately 14%) better at texture filtering than the GeForce GTX 850M. (explain)

Radeon HD 4890 1GB		40000 Mtexels/sec
GeForce GTX 850M		35040 Mtexels/sec
	Difference: 4960 (14%)

Pixel Rate

If using a high resolution is important to you, then the Radeon HD 4890 1GB is a better choice, though only just barely. (explain)

Radeon HD 4890 1GB		16000 Mpixels/sec
GeForce GTX 850M		14016 Mpixels/sec
	Difference: 1984 (14%)

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 max amount of data (counted in MB per second) that can be transferred across the external memory interface in a second. It's worked out by multiplying the bus width by its memory speed. If it uses DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the faster 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 applied in one second. This number is worked out by multiplying the total texture units by the core speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied per second.

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on many other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.