GeForce 8800 Ultra vs Radeon HD 4870 512MB

Intro

Compare that to the Radeon HD 4870 512MB, which has a core clock speed of 750 MHz and a GDDR5 memory speed of 900 MHz. It also uses a 256-bit bus, and uses a 55 nm design. It features 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4870 512MB		150 Watts
GeForce 8800 Ultra		171 Watts
	Difference: 21 Watts (14%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 4870 512MB will be 11% quicker than the GeForce 8800 Ultra overall, because of its higher data rate. (explain)

Radeon HD 4870 512MB		115200 MB/sec
GeForce 8800 Ultra		103680 MB/sec
	Difference: 11520 (11%)

Texel Rate

The GeForce 8800 Ultra is quite a bit (more or less 31%) better at AF than the Radeon HD 4870 512MB. (explain)

GeForce 8800 Ultra		39168 Mtexels/sec
Radeon HD 4870 512MB		30000 Mtexels/sec
	Difference: 9168 (31%)

Pixel Rate

The GeForce 8800 Ultra should be quite a bit (approximately 22%) faster with regards to FSAA than the Radeon HD 4870 512MB, and also should be capable of handling higher resolutions better. (explain)

GeForce 8800 Ultra		14688 Mpixels/sec
Radeon HD 4870 512MB		12000 Mpixels/sec
	Difference: 2688 (22%)

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 data (in units of MB per second) that can be transferred across the external memory interface in a second. It is calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR type RAM, the result should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This figure is worked out 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 one second.

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card could possibly write to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output 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 maximum fill rate.