GeForce 8800 GTX vs Radeon HD 7990

Intro

Compare all of that to the Radeon HD 7990, which comes with core speeds of 950 MHz on the GPU, and 1500 MHz on the 3072 MB of GDDR5 RAM. It features 2048 SPUs along with 128 Texture Address Units and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 GTX		155 Watts
Radeon HD 7990		375 Watts
	Difference: 220 Watts (142%)

Memory Bandwidth

The Radeon HD 7990 should theoretically perform much faster than the GeForce 8800 GTX in general. (explain)

Radeon HD 7990		576000 MB/sec
GeForce 8800 GTX		86400 MB/sec
	Difference: 489600 (567%)

Texel Rate

The Radeon HD 7990 should be much (more or less 561%) faster with regards to anisotropic filtering than the GeForce 8800 GTX. (explain)

Radeon HD 7990		243200 Mtexels/sec
GeForce 8800 GTX		36800 Mtexels/sec
	Difference: 206400 (561%)

Pixel Rate

The Radeon HD 7990 will be quite a bit (about 341%) faster with regards to FSAA than the GeForce 8800 GTX, and also able to handle higher resolutions while still performing well. (explain)

Radeon HD 7990		60800 Mpixels/sec
GeForce 8800 GTX		13800 Mpixels/sec
	Difference: 47000 (341%)

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 (counted in MB per second) that can be transported past the external memory interface within a second. The number is calculated by multiplying the bus width by its memory clock speed. In the case of DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly write to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.