GeForce 9800 GX2 vs Radeon HD 4870 1GB

Intro

Compare those specifications to the Radeon HD 4870 1GB, which makes use of a 55 nm design. AMD has set the core speed at 750 MHz. The GDDR5 RAM is set to run at a speed of 900 MHz on this particular model. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4870 1GB		150 Watts
GeForce 9800 GX2		197 Watts
	Difference: 47 Watts (31%)

Memory Bandwidth

The GeForce 9800 GX2, in theory, should be a bit faster than the Radeon HD 4870 1GB overall. (explain)

GeForce 9800 GX2		128000 MB/sec
Radeon HD 4870 1GB		115200 MB/sec
	Difference: 12800 (11%)

Texel Rate

The GeForce 9800 GX2 should be quite a bit (approximately 156%) faster with regards to texture filtering than the Radeon HD 4870 1GB. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
Radeon HD 4870 1GB		30000 Mtexels/sec
	Difference: 46800 (156%)

Pixel Rate

The GeForce 9800 GX2 will be a lot (more or less 60%) better at anti-aliasing than the Radeon HD 4870 1GB, and also will be able to handle higher resolutions without slowing down too much. (explain)

GeForce 9800 GX2		19200 Mpixels/sec
Radeon HD 4870 1GB		12000 Mpixels/sec
	Difference: 7200 (60%)

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 maximum amount of data (in units of MB per second) that can be transferred over the external memory interface in one second. It's calculated by multiplying the interface width by the speed of its memory. If the card has DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster 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 texture map elements (texels) that are applied per second. This number is worked out by multiplying the total number of texture units of the card by the core speed of the chip. The better this number, the better the graphics card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

Pixel Rate: Pixel rate is the most pixels the graphics card could possibly record to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.