GeForce GTS 450 vs Radeon HD 4850 X2 1GB

Intro

Compare all that to the Radeon HD 4850 X2 1GB, which makes use of a 55 nm design. AMD has set the core speed at 625 MHz. The GDDR3 RAM runs at a frequency of 993 MHz on this card. It features 800(160x5) SPUs along with 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTS 450		106 Watts
Radeon HD 4850 X2 1GB		250 Watts
	Difference: 144 Watts (136%)

Memory Bandwidth

In theory, the Radeon HD 4850 X2 1GB will be 120% faster than the GeForce GTS 450 overall, because of its higher data rate. (explain)

Radeon HD 4850 X2 1GB		127104 MB/sec
GeForce GTS 450		57728 MB/sec
	Difference: 69376 (120%)

Texel Rate

The Radeon HD 4850 X2 1GB will be much (more or less 100%) more effective at AF than the GeForce GTS 450. (explain)

Radeon HD 4850 X2 1GB		50000 Mtexels/sec
GeForce GTS 450		25056 Mtexels/sec
	Difference: 24944 (100%)

Pixel Rate

The Radeon HD 4850 X2 1GB is quite a bit (about 60%) faster with regards to anti-aliasing than the GeForce GTS 450, and should be able to handle higher resolutions more effectively. (explain)

Radeon HD 4850 X2 1GB		20000 Mpixels/sec
GeForce GTS 450		12528 Mpixels/sec
	Difference: 7472 (60%)

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: Bandwidth is the max amount of information (measured in MB per second) that can be transferred past the external memory interface in one second. The number is worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR memory, it should be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly record to the 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 card's clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel rate also depends on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.