GeForce GT 450 (OEM) vs Radeon HD 4790

Intro

Compare that to the Radeon HD 4790, which has a core clock frequency of 600 MHz and a GDDR5 memory speed of 800 MHz. It also makes use of 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

Theoretically speaking, the Radeon HD 4790 should be 7% faster than the GeForce GT 450 (OEM) overall, because of its higher data rate. (explain)

Radeon HD 4790		102400 MB/sec
GeForce GT 450 (OEM)		96000 MB/sec
	Difference: 6400 (7%)

Texel Rate

The Radeon HD 4790 will be a small bit (approximately 1%) better at texture filtering than the GeForce GT 450 (OEM). (explain)

Radeon HD 4790		19200 Mtexels/sec
GeForce GT 450 (OEM)		18960 Mtexels/sec
	Difference: 240 (1%)

Pixel Rate

The GeForce GT 450 (OEM) will be quite a bit (approximately 98%) better at FSAA than the Radeon HD 4790, and able to handle higher resolutions while still performing well. (explain)

GeForce GT 450 (OEM)		18960 Mpixels/sec
Radeon HD 4790		9600 Mpixels/sec
	Difference: 9360 (98%)

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 max amount of information (measured in megabytes per second) that can be moved past the external memory interface in a second. It's worked out by multiplying the interface width by the speed of its memory. If it uses DDR type RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.