GeForce GTX 275 vs Radeon HD 4870 512MB

Intro

Compare those specifications to the Radeon HD 4870 512MB, which uses a 55 nm design. AMD has set the core frequency at 750 MHz. The GDDR5 RAM is set to run at a speed of 900 MHz on this specific model. 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)

Radeon HD 4870 512MB		150 Watts
GeForce GTX 275		219 Watts
	Difference: 69 Watts (46%)

Memory Bandwidth

In theory, the GeForce GTX 275 should perform a small bit faster than the Radeon HD 4870 512MB in general. (explain)

GeForce GTX 275		127008 MB/sec
Radeon HD 4870 512MB		115200 MB/sec
	Difference: 11808 (10%)

Texel Rate

The GeForce GTX 275 is quite a bit (more or less 69%) faster with regards to anisotropic filtering than the Radeon HD 4870 512MB. (explain)

GeForce GTX 275		50640 Mtexels/sec
Radeon HD 4870 512MB		30000 Mtexels/sec
	Difference: 20640 (69%)

Pixel Rate

The GeForce GTX 275 will be much (about 48%) faster with regards to AA than the Radeon HD 4870 512MB, and able to handle higher screen resolutions better. (explain)

GeForce GTX 275		17724 Mpixels/sec
Radeon HD 4870 512MB		12000 Mpixels/sec
	Difference: 5724 (48%)

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: Bandwidth is the maximum amount of information (measured in megabytes per second) that can be transported across the external memory interface in one second. It's calculated by multiplying the card's interface width by its memory speed. If the card has DDR memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics card could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.