GeForce 9800 GX2 vs Radeon HD 7770

Intro

Compare those specifications to the Radeon HD 7770, which makes use of a 28 nm design. AMD has clocked the core speed at 1000 MHz. The GDDR5 RAM works at a frequency of 1125 MHz on this particular model. It features 640 SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
GeForce 9800 GX2		197 Watts
	Difference: 117 Watts (146%)

Memory Bandwidth

In theory, the GeForce 9800 GX2 should be quite a bit faster than the Radeon HD 7770 in general. (explain)

GeForce 9800 GX2		128000 MB/sec
Radeon HD 7770		72000 MB/sec
	Difference: 56000 (78%)

Texel Rate

The GeForce 9800 GX2 is a lot (more or less 92%) more effective at texture filtering than the Radeon HD 7770. (explain)

GeForce 9800 GX2		76800 Mtexels/sec
Radeon HD 7770		40000 Mtexels/sec
	Difference: 36800 (92%)

Pixel Rate

If running with a high resolution is important to you, then the GeForce 9800 GX2 is the winner, though only just barely. (explain)

GeForce 9800 GX2		19200 Mpixels/sec
Radeon HD 7770		16000 Mpixels/sec
	Difference: 3200 (20%)

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 information (measured in megabytes per second) that can be transported past the external memory interface within a second. It's calculated by multiplying the card's interface width by its memory clock speed. In the case of DDR type memory, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one second. This number is worked out by multiplying the total texture units by the core clock speed of the chip. The higher the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

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