Radeon HD 4850 X2 512MB vs Radeon HD 6670 (OEM) 1GB

Intro

Compare all of that to the Radeon HD 6670 (OEM) 1GB, which features a core clock frequency of 800 MHz and a GDDR5 memory speed of 1000 MHz. It also uses a 128-bit bus, and makes use of a 40 nm design. It is comprised of 480 SPUs, 24 TAUs, and 8 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 6670 (OEM) 1GB		63 Watts
Radeon HD 4850 X2 512MB		250 Watts
	Difference: 187 Watts (297%)

Memory Bandwidth

Theoretically, the Radeon HD 4850 X2 512MB should be a lot faster than the Radeon HD 6670 (OEM) 1GB in general. (explain)

Radeon HD 4850 X2 512MB		127104 MB/sec
Radeon HD 6670 (OEM) 1GB		64000 MB/sec
	Difference: 63104 (99%)

Texel Rate

The Radeon HD 4850 X2 512MB will be a lot (about 160%) better at anisotropic filtering than the Radeon HD 6670 (OEM) 1GB. (explain)

Radeon HD 4850 X2 512MB		50000 Mtexels/sec
Radeon HD 6670 (OEM) 1GB		19200 Mtexels/sec
	Difference: 30800 (160%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 4850 X2 512MB is a better choice, and very much so. (explain)

Radeon HD 4850 X2 512MB		20000 Mpixels/sec
Radeon HD 6670 (OEM) 1GB		6400 Mpixels/sec
	Difference: 13600 (213%)

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 largest amount of information (counted in megabytes per second) that can be moved past the external memory interface in a second. It is worked out by multiplying the bus width by its memory clock speed. In the case of DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the memory bandwidth, 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 can be applied per second. This figure is worked out by multiplying the total texture units 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 processed per second.

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