Radeon HD 3870 X2 512MB vs Radeon HD 4830 1GB

Intro

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

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

Performance-wise, the Radeon HD 3870 X2 512MB should theoretically be quite a bit superior to the Radeon HD 4830 1GB in general. (explain)

Radeon HD 3870 X2 512MB		115200 MB/sec
Radeon HD 4830 1GB		57600 MB/sec
	Difference: 57600 (100%)

Texel Rate

The Radeon HD 3870 X2 512MB is quite a bit (approximately 43%) more effective at AF than the Radeon HD 4830 1GB. (explain)

Radeon HD 3870 X2 512MB		26400 Mtexels/sec
Radeon HD 4830 1GB		18400 Mtexels/sec
	Difference: 8000 (43%)

Pixel Rate

If using high levels of AA is important to you, then the Radeon HD 3870 X2 512MB is the winner, and very much so. (explain)

Radeon HD 3870 X2 512MB		26400 Mpixels/sec
Radeon HD 4830 1GB		9200 Mpixels/sec
	Difference: 17200 (187%)

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.

One or more cards in this comparison are multi-core. This means that their bandwidth, texel and pixel rates are theoretically doubled - this does not mean the card will actually perform twice as fast, but only that it should in theory be able to. Actual game benchmarks will give a more accurate idea of what it's capable of.

Price Comparison

Specifications

Memory Bandwidth: Memory bandwidth is the maximum amount of data (measured in MB per second) that can be transferred past the external memory interface in one second. It's calculated by multiplying the card's interface width by its memory clock speed. If it uses DDR RAM, the result should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the bandwidth is, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied per second. This is worked out by multiplying the total texture units by the core speed of the chip. The higher 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 a second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip can possibly record to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of colour 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 fill rate also depends on quite a few other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.