GeForce GT 420 vs Radeon HD 4830 512MB

Intro

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

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 420		50 Watts
Radeon HD 4830 512MB		95 Watts
	Difference: 45 Watts (90%)

Memory Bandwidth

The Radeon HD 4830 512MB, in theory, should perform much faster than the GeForce GT 420 in general. (explain)

Radeon HD 4830 512MB		57600 MB/sec
GeForce GT 420		28800 MB/sec
	Difference: 28800 (100%)

Texel Rate

The Radeon HD 4830 512MB will be much (approximately 229%) more effective at texture filtering than the GeForce GT 420. (explain)

Radeon HD 4830 512MB		18400 Mtexels/sec
GeForce GT 420		5600 Mtexels/sec
	Difference: 12800 (229%)

Pixel Rate

The Radeon HD 4830 512MB should be much (about 229%) faster with regards to anti-aliasing than the GeForce GT 420, and will be able to handle higher resolutions while still performing well. (explain)

Radeon HD 4830 512MB		9200 Mpixels/sec
GeForce GT 420		2800 Mpixels/sec
	Difference: 6400 (229%)

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

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This figure is calculated by multiplying the total texture units by the core clock speed of the chip. The higher this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of ROPs by the the core 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 is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.