GeForce GTS 250 512MB vs Radeon HD 4850 X2 512MB

Intro

Compare that to the Radeon HD 4850 X2 512MB, which has a core clock speed of 625 MHz and a GDDR3 memory frequency of 993 MHz. It also uses a 256-bit memory bus, and makes use of a 55 nm design. It is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.

Display Graphs

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Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTS 250 512MB		145 Watts
Radeon HD 4850 X2 512MB		250 Watts
	Difference: 105 Watts (72%)

Memory Bandwidth

The Radeon HD 4850 X2 512MB should theoretically perform quite a bit faster than the GeForce GTS 250 512MB in general. (explain)

Radeon HD 4850 X2 512MB		127104 MB/sec
GeForce GTS 250 512MB		70400 MB/sec
	Difference: 56704 (81%)

Texel Rate

The Radeon HD 4850 X2 512MB will be a small bit (more or less 6%) better at AF than the GeForce GTS 250 512MB. (explain)

Radeon HD 4850 X2 512MB		50000 Mtexels/sec
GeForce GTS 250 512MB		47232 Mtexels/sec
	Difference: 2768 (6%)

Pixel Rate

The Radeon HD 4850 X2 512MB should be quite a bit (approximately 69%) faster with regards to full screen anti-aliasing than the GeForce GTS 250 512MB, and should be capable of handling higher screen resolutions more effectively. (explain)

Radeon HD 4850 X2 512MB		20000 Mpixels/sec
GeForce GTS 250 512MB		11808 Mpixels/sec
	Difference: 8192 (69%)

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 maximum amount of information (counted in megabytes per second) that can be transported across the external memory interface in one second. The number is calculated by multiplying the interface width by its memory clock speed. If the card has DDR memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be processed in one second. This figure is calculated by multiplying the total number 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 handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.