GeForce 9800 GT 1GB vs Radeon HD 4830 512MB

Intro

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

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4830 512MB		95 Watts
GeForce 9800 GT 1GB		105 Watts
	Difference: 10 Watts (11%)

Memory Bandwidth

Both cards have exactly the same memory bandwidth, so in theory they should perform exactly the same. (explain)

Texel Rate

The GeForce 9800 GT 1GB is much (about 83%) faster with regards to texture filtering than the Radeon HD 4830 512MB. (explain)

GeForce 9800 GT 1GB		33600 Mtexels/sec
Radeon HD 4830 512MB		18400 Mtexels/sec
	Difference: 15200 (83%)

Pixel Rate

If running with a high screen resolution is important to you, then the GeForce 9800 GT 1GB is a better choice, though not by far. (explain)

GeForce 9800 GT 1GB		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: Memory bandwidth is the maximum amount of information (in units of MB per second) that can be moved across the external memory interface in a second. The number is calculated by multiplying the bus width by its memory clock speed. If it uses DDR type memory, it must be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the bandwidth is, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be processed in one second. This figure is worked out by multiplying the total number of texture units by the core clock speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of colour ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.