GeForce GTX 850M vs Radeon HD 4870 512MB

Intro

Compare those specs to the Radeon HD 4870 512MB, which uses a 55 nm design. AMD has clocked the core frequency at 750 MHz. The GDDR5 RAM is set to run at a frequency of 900 MHz on this particular card. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 850M		40 Watts
Radeon HD 4870 512MB		150 Watts
	Difference: 110 Watts (275%)

Memory Bandwidth

In theory, the Radeon HD 4870 512MB should perform a lot faster than the GeForce GTX 850M in general. (explain)

Radeon HD 4870 512MB		115200 MB/sec
GeForce GTX 850M		32000 MB/sec
	Difference: 83200 (260%)

Texel Rate

The GeForce GTX 850M will be just a bit (approximately 17%) faster with regards to AF than the Radeon HD 4870 512MB. (explain)

GeForce GTX 850M		35040 Mtexels/sec
Radeon HD 4870 512MB		30000 Mtexels/sec
	Difference: 5040 (17%)

Pixel Rate

The GeForce GTX 850M is a little bit (about 17%) better at AA than the Radeon HD 4870 512MB, and also will be able to handle higher resolutions without losing too much performance. (explain)

GeForce GTX 850M		14016 Mpixels/sec
Radeon HD 4870 512MB		12000 Mpixels/sec
	Difference: 2016 (17%)

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 (in units of MB per second) that can be transported over the external memory interface in one second. The number is worked out by multiplying the card's interface width by its memory clock speed. In the case of DDR type RAM, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the better 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 processed in one second. This is calculated 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 processed in one second.

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill 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 get to the max fill rate.