GeForce 920M vs Radeon HD 4870 X2

Intro

Compare that to the Radeon HD 4870 X2, which features core clock speeds of 750 MHz on the GPU, and 900 MHz on the 1024 MB of GDDR5 RAM. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon HD 4870 X2 is 1500% quicker than the GeForce 920M in general, because of its greater bandwidth. (explain)

Radeon HD 4870 X2		230400 MB/sec
GeForce 920M		14400 MB/sec
	Difference: 216000 (1500%)

Texel Rate

The Radeon HD 4870 X2 should be quite a bit (about 97%) faster with regards to anisotropic filtering than the GeForce 920M. (explain)

Radeon HD 4870 X2		60000 Mtexels/sec
GeForce 920M		30528 Mtexels/sec
	Difference: 29472 (97%)

Pixel Rate

The Radeon HD 4870 X2 is much (approximately 214%) faster with regards to full screen anti-aliasing than the GeForce 920M, and will be able to handle higher resolutions without losing too much performance. (explain)

Radeon HD 4870 X2		24000 Mpixels/sec
GeForce 920M		7632 Mpixels/sec
	Difference: 16368 (214%)

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: Memory bandwidth is the largest amount of information (measured in megabytes per second) that can be transported past the external memory interface in one second. It is calculated by multiplying the bus width by its memory clock speed. If the card has DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. 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 can be applied in one second. This is calculated by multiplying the total number of texture units of the card by the core speed of the chip. The higher the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the max fill rate.