Radeon HD 4830 1GB vs Radeon HD 7870

Intro

Compare those specifications to the Radeon HD 7870, which has GPU core speed of 1000 MHz, and 2048 MB of GDDR5 RAM set to run at 1200 MHz through a 256-bit bus. It also is made up of 1280 SPUs, 80 TAUs, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4830 1GB		95 Watts
Radeon HD 7870		175 Watts
	Difference: 80 Watts (84%)

Memory Bandwidth

The Radeon HD 7870, in theory, should perform a lot faster than the Radeon HD 4830 1GB overall. (explain)

Radeon HD 7870		153600 MB/sec
Radeon HD 4830 1GB		57600 MB/sec
	Difference: 96000 (167%)

Texel Rate

The Radeon HD 7870 should be much (more or less 335%) more effective at texture filtering than the Radeon HD 4830 1GB. (explain)

Radeon HD 7870		80000 Mtexels/sec
Radeon HD 4830 1GB		18400 Mtexels/sec
	Difference: 61600 (335%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon HD 7870 is a better choice, and very much so. (explain)

Radeon HD 7870		32000 Mpixels/sec
Radeon HD 4830 1GB		9200 Mpixels/sec
	Difference: 22800 (248%)

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 (counted in megabytes per second) that can be transported across the external memory interface within a second. It's calculated by multiplying the bus width by its memory speed. If the card has DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied in one second. This figure is worked out by multiplying the total number of texture units of the card by the core 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 applied in one second.

Pixel Rate: Pixel rate is the maximum number of pixels the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to reach the maximum fill rate.