GeForce 9800 GT 512MB vs Radeon HD 4830 512MB

Intro

Compare those specifications to the Radeon HD 4830 512MB, which comes with a core clock speed of 575 MHz and a GDDR3 memory speed of 900 MHz. It also features a 256-bit memory bus, and makes use of a 55 nm design. It is comprised of 640(128x5) SPUs, 32 Texture Address Units, and 16 ROPs.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4830 512MB		95 Watts
GeForce 9800 GT 512MB		105 Watts
	Difference: 10 Watts (11%)

Memory Bandwidth

Both cards have the exact same bandwidth, so theoretically they should have identical performance. (explain)

Texel Rate

The GeForce 9800 GT 512MB should be a lot (about 83%) better at AF than the Radeon HD 4830 512MB. (explain)

GeForce 9800 GT 512MB		33600 Mtexels/sec
Radeon HD 4830 512MB		18400 Mtexels/sec
	Difference: 15200 (83%)

Pixel Rate

If using a high resolution is important to you, then the GeForce 9800 GT 512MB is the winner, though not by far. (explain)

GeForce 9800 GT 512MB		9600 Mpixels/sec
Radeon HD 4830 512MB		9200 Mpixels/sec
	Difference: 400 (4%)

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 maximum amount of data (measured in megabytes per second) that can be moved past the external memory interface in a second. The number is worked out by multiplying the bus width by its memory speed. In the case of DDR type memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. 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 number of texture map elements (texels) that are processed per second. This number is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The better the texel rate, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly write to the local memory in one second - measured in millions of pixels per second. The number is calculated by multiplying the amount of ROPs by the the card's clock speed. 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 output rate also depends on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.