GeForce 9800 GTX vs Radeon HD 3870 1GB

Intro

Compare those specs to the Radeon HD 3870 1GB, which uses a 55 nm design. AMD has set the core frequency at 775 MHz. The GDDR4 RAM runs at a speed of 1125 MHz on this model. It features 320(64x5) SPUs along with 16 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 3870 1GB		106 Watts
GeForce 9800 GTX		140 Watts
	Difference: 34 Watts (32%)

Memory Bandwidth

As far as performance goes, the Radeon HD 3870 1GB should in theory be a bit better than the GeForce 9800 GTX overall. (explain)

Radeon HD 3870 1GB		72000 MB/sec
GeForce 9800 GTX		70400 MB/sec
	Difference: 1600 (2%)

Texel Rate

The GeForce 9800 GTX is a lot (more or less 248%) more effective at anisotropic filtering than the Radeon HD 3870 1GB. (explain)

GeForce 9800 GTX		43200 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 30800 (248%)

Pixel Rate

The Radeon HD 3870 1GB is a small bit (approximately 15%) more effective at FSAA than the GeForce 9800 GTX, and also will be capable of handling higher screen resolutions while still performing well. (explain)

Radeon HD 3870 1GB		12400 Mpixels/sec
GeForce 9800 GTX		10800 Mpixels/sec
	Difference: 1600 (15%)

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: Bandwidth is the max amount of data (counted in megabytes per second) that can be moved across the external memory interface within a second. The number is worked out by multiplying the card's bus width by its memory clock speed. In the case of DDR type RAM, it must be multiplied by 2 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 AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied per second. This figure is worked out by multiplying the total amount of texture units by the core speed of the chip. The higher the texel rate, the better the 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 that the graphics chip could possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate also depends on quite a few other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.