GeForce 9800 GX2 vs Radeon HD 4870 X2

Intro

Compare all of that to the Radeon HD 4870 X2, which makes use of a 55 nm design. AMD has set the core speed at 750 MHz. The GDDR5 memory is set to run at a speed of 900 MHz on this specific card. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 9800 GX2		197 Watts
Radeon HD 4870 X2		350 Watts
	Difference: 153 Watts (78%)

Memory Bandwidth

As far as performance goes, the Radeon HD 4870 X2 should in theory be a lot superior to the GeForce 9800 GX2 overall. (explain)

Radeon HD 4870 X2		230400 MB/sec
GeForce 9800 GX2		128000 MB/sec
	Difference: 102400 (80%)

Texel Rate

The GeForce 9800 GX2 is quite a bit (approximately 28%) more effective at anisotropic filtering than the Radeon HD 4870 X2. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
Radeon HD 4870 X2		60000 Mtexels/sec
	Difference: 16800 (28%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon HD 4870 X2 is superior to the GeForce 9800 GX2, by a large margin. (explain)

Radeon HD 4870 X2		24000 Mpixels/sec
GeForce 9800 GX2		19200 Mpixels/sec
	Difference: 4800 (25%)

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 max amount of data (counted in megabytes per second) that can be moved across the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory clock speed. In the case of DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, 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 amount of texture map elements (texels) that can be applied in one second. This figure is worked out by multiplying the total amount of 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 its local memory in one second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.