GeForce GTX 850M vs Radeon HD 4670 512MB

Intro

Compare those specifications to the Radeon HD 4670 512MB, which features a clock speed of 750 MHz and a GDDR4/GDDR3/DDR3/DDR2 memory speed of 1000 MHz. It also uses a 128-bit bus, and makes use of a 55 nm design. It features 320(64x5) SPUs, 32 Texture Address Units, and 8 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 850M		40 Watts
Radeon HD 4670 512MB		70 Watts
	Difference: 30 Watts (75%)

Memory Bandwidth

Both cards have the exact same memory bandwidth, so in theory they should perform the same. (explain)

Texel Rate

The GeForce GTX 850M is much (about 46%) better at texture filtering than the Radeon HD 4670 512MB. (explain)

GeForce GTX 850M		35040 Mtexels/sec
Radeon HD 4670 512MB		24000 Mtexels/sec
	Difference: 11040 (46%)

Pixel Rate

The GeForce GTX 850M is a lot (about 134%) more effective at full screen anti-aliasing than the Radeon HD 4670 512MB, and should be capable of handling higher screen resolutions without losing too much performance. (explain)

GeForce GTX 850M		14016 Mpixels/sec
Radeon HD 4670 512MB		6000 Mpixels/sec
	Difference: 8016 (134%)

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 max amount of information (counted in megabytes per second) that can be transferred past the external memory interface in a second. It's worked out by multiplying the card's interface width by its memory clock speed. If it uses DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the most pixels that the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on lots of other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.