GeForce 8600 GT 1GB DDR2 vs Radeon HD 6990

Intro

Compare all that to the Radeon HD 6990, which makes use of a 40 nm design. AMD has set the core frequency at 830 MHz. The GDDR5 RAM runs at a frequency of 1250 MHz on this card. It features 1536 SPUs along with 96 Texture Address Units and 32 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8600 GT 1GB DDR2		47 Watts
Radeon HD 6990		375 Watts
	Difference: 328 Watts (698%)

Memory Bandwidth

The Radeon HD 6990, in theory, should perform a lot faster than the GeForce 8600 GT 1GB DDR2 overall. (explain)

Radeon HD 6990		320000 MB/sec
GeForce 8600 GT 1GB DDR2		12800 MB/sec
	Difference: 307200 (2400%)

Texel Rate

The Radeon HD 6990 is much (approximately 1744%) faster with regards to AF than the GeForce 8600 GT 1GB DDR2. (explain)

Radeon HD 6990		159360 Mtexels/sec
GeForce 8600 GT 1GB DDR2		8640 Mtexels/sec
	Difference: 150720 (1744%)

Pixel Rate

The Radeon HD 6990 is quite a bit (approximately 1130%) more effective at full screen anti-aliasing than the GeForce 8600 GT 1GB DDR2, and should be capable of handling higher screen resolutions better. (explain)

Radeon HD 6990		53120 Mpixels/sec
GeForce 8600 GT 1GB DDR2		4320 Mpixels/sec
	Difference: 48800 (1130%)

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: Bandwidth is the maximum amount of information (counted 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 speed. In the case of DDR memory, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the 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 processed in one second. This is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better this number, the better the 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 most pixels that the graphics chip can possibly record to the local memory in one second - measured in millions of pixels per second. The number is worked out by multiplying the number of ROPs by the clock speed of the card. 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, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the max fill rate.