Radeon HD 4790 vs Radeon HD 6670 (OEM) 1GB

Intro

Compare those specs to the Radeon HD 6670 (OEM) 1GB, which uses a 40 nm design. AMD has clocked the core speed at 800 MHz. The GDDR5 memory is set to run at a frequency of 1000 MHz on this model. It features 480 SPUs along with 24 TAUs and 8 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon HD 4790 will be 60% faster than the Radeon HD 6670 (OEM) 1GB in general, because of its higher bandwidth. (explain)

Radeon HD 4790		102400 MB/sec
Radeon HD 6670 (OEM) 1GB		64000 MB/sec
	Difference: 38400 (60%)

Texel Rate

Both cards have the exact same texel fill rate, so theoretically they should perform equally good at at anisotropic filtering. (explain)

Pixel Rate

If using a high resolution is important to you, then the Radeon HD 4790 is the winner, by a large margin. (explain)

Radeon HD 4790		9600 Mpixels/sec
Radeon HD 6670 (OEM) 1GB		6400 Mpixels/sec
	Difference: 3200 (50%)

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: Memory bandwidth is the largest amount of information (measured in megabytes per second) that can be moved over the external memory interface in a second. It's calculated by multiplying the card's bus width by its memory speed. In the case of DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This is worked out by multiplying the total amount of texture units of the card by the core speed of the chip. The higher the texel rate, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the most pixels the video card could possibly write to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on many other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the potential to reach the maximum fill rate.