GeForce 8600 GT 512MB DDR2 vs Radeon HD 7870 XT

Intro

Compare all of that to the Radeon HD 7870 XT, which comes with a core clock speed of 925 MHz and a GDDR5 memory frequency of 1500 MHz. It also uses a 256-bit bus, and makes use of a 28 nm design. It features 1536 SPUs, 96 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8600 GT 512MB DDR2		47 Watts
Radeon HD 7870 XT		185 Watts
	Difference: 138 Watts (294%)

Memory Bandwidth

The Radeon HD 7870 XT should in theory be quite a bit faster than the GeForce 8600 GT 512MB DDR2 in general. (explain)

Radeon HD 7870 XT		192000 MB/sec
GeForce 8600 GT 512MB DDR2		12800 MB/sec
	Difference: 179200 (1400%)

Texel Rate

The Radeon HD 7870 XT should be a lot (approximately 928%) better at texture filtering than the GeForce 8600 GT 512MB DDR2. (explain)

Radeon HD 7870 XT		88800 Mtexels/sec
GeForce 8600 GT 512MB DDR2		8640 Mtexels/sec
	Difference: 80160 (928%)

Pixel Rate

If using lots of anti-aliasing is important to you, then the Radeon HD 7870 XT is the winner, by far. (explain)

Radeon HD 7870 XT		29600 Mpixels/sec
GeForce 8600 GT 512MB DDR2		4320 Mpixels/sec
	Difference: 25280 (585%)

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.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of information (in units of megabytes per second) that can be transported past the external memory interface within a second. It is worked out by multiplying the bus width by its memory speed. If it uses DDR type memory, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels the video card can possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate also depends on quite a few other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.