GeForce GT 340 vs Radeon HD 4790

Intro

Compare all of that to the Radeon HD 4790, which features a core clock speed of 600 MHz and a GDDR5 memory frequency of 800 MHz. It also uses a 256-bit memory bus, and makes use of a 55 nm design. It features 640(128x5) SPUs, 32 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Memory Bandwidth

In theory, the Radeon HD 4790 will be 88% quicker than the GeForce GT 340 in general, because of its greater data rate. (explain)

Radeon HD 4790		102400 MB/sec
GeForce GT 340		54400 MB/sec
	Difference: 48000 (88%)

Texel Rate

The Radeon HD 4790 is a little bit (more or less 9%) faster with regards to anisotropic filtering than the GeForce GT 340. (explain)

Radeon HD 4790		19200 Mtexels/sec
GeForce GT 340		17600 Mtexels/sec
	Difference: 1600 (9%)

Pixel Rate

The Radeon HD 4790 will be a lot (more or less 118%) more effective at FSAA than the GeForce GT 340, and should be able to handle higher resolutions better. (explain)

Radeon HD 4790		9600 Mpixels/sec
GeForce GT 340		4400 Mpixels/sec
	Difference: 5200 (118%)

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 maximum amount of information (measured in megabytes per second) that can be transported across the external memory interface in a second. It's worked out by multiplying the interface width by its memory speed. In the case of DDR RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The better 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 number is calculated by multiplying the total texture units by the core clock speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

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