GeForce 9800 GX2 vs Radeon HD 3870 512MB

Intro

Compare those specifications to the Radeon HD 3870 512MB, which makes use of a 55 nm design. AMD has set the core frequency at 775 MHz. The GDDR3 RAM works at a frequency of 900 MHz on this card. It features 320(64x5) SPUs along with 16 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3870 512MB		106 Watts
GeForce 9800 GX2		197 Watts
	Difference: 91 Watts (86%)

Memory Bandwidth

As far as performance goes, the GeForce 9800 GX2 should in theory be a lot superior to the Radeon HD 3870 512MB overall. (explain)

GeForce 9800 GX2		128000 MB/sec
Radeon HD 3870 512MB		57600 MB/sec
	Difference: 70400 (122%)

Texel Rate

The GeForce 9800 GX2 should be a lot (approximately 519%) more effective at anisotropic filtering than the Radeon HD 3870 512MB. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
Radeon HD 3870 512MB		12400 Mtexels/sec
	Difference: 64400 (519%)

Pixel Rate

The GeForce 9800 GX2 should be much (approximately 55%) more effective at AA than the Radeon HD 3870 512MB, and also should be able to handle higher resolutions without slowing down too much. (explain)

GeForce 9800 GX2		19200 Mpixels/sec
Radeon HD 3870 512MB		12400 Mpixels/sec
	Difference: 6800 (55%)

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 data (measured in megabytes per second) that can be transported over the external memory interface in one second. It is worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This number is calculated by multiplying the total texture units of the card by the core speed of the chip. The higher the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.