GeForce 820M vs Radeon HD 3850 X2

Intro

Compare all of that to the Radeon HD 3850 X2, which comes with a clock speed of 668 MHz and a GDDR3 memory frequency of 828 MHz. It also features a 256-bit bus, and makes use of a 55 nm design. It features 320(64x5) SPUs, 16 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon HD 3850 X2 should theoretically be quite a bit superior to the GeForce 820M in general. (explain)

Radeon HD 3850 X2		105984 MB/sec
GeForce 820M		16000 MB/sec
	Difference: 89984 (562%)

Texel Rate

The Radeon HD 3850 X2 is much (about 86%) better at AF than the GeForce 820M. (explain)

Radeon HD 3850 X2		21376 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 9872 (86%)

Pixel Rate

If running with lots of anti-aliasing is important to you, then the Radeon HD 3850 X2 is superior to the GeForce 820M, by far. (explain)

Radeon HD 3850 X2		21376 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 18500 (643%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Bandwidth is the largest amount of data (measured in megabytes per second) that can be moved past the external memory interface in a second. The number is worked out by multiplying the interface width by its memory speed. If the card has DDR type RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster 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 number of texture map elements (texels) that are applied in one second. This number is calculated by multiplying the total number of texture units by the core clock speed of the chip. The better the texel rate, the better the graphics 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 maximum amount of pixels the graphics card can possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.