GeForce 9800 GT 512MB vs Radeon HD 4830 1GB

Intro

Compare those specs to the Radeon HD 4830 1GB, which comes with a clock frequency of 575 MHz and a GDDR4 memory speed of 900 MHz. It also features a 256-bit bus, and uses a 55 nm design. It is comprised of 640(128x5) SPUs, 32 TAUs, and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

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

Memory Bandwidth

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

Texel Rate

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

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

Pixel Rate

If running with a high resolution is important to you, then the GeForce 9800 GT 512MB is the winner, though only just barely. (explain)

GeForce 9800 GT 512MB		9600 Mpixels/sec
Radeon HD 4830 1GB		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 largest amount of information (counted in MB per second) that can be transported past the external memory interface in a second. It's worked out by multiplying the interface width by the speed of its memory. If the card has DDR type memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This number is worked out by multiplying the total 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 the graphics card can possibly write to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core speed of the card. 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 fill rate is also dependant on many other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.