GeForce GTX 295 vs Radeon HD 4870 2GB

Intro

Compare that to the Radeon HD 4870 2GB, which has a clock speed of 750 MHz and a GDDR5 memory frequency of 900 MHz. It also features a 256-bit memory bus, and uses a 55 nm design. It is comprised of 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4870 2GB		150 Watts
GeForce GTX 295		289 Watts
	Difference: 139 Watts (93%)

Memory Bandwidth

In theory, the GeForce GTX 295 should be 94% quicker than the Radeon HD 4870 2GB overall, due to its higher data rate. (explain)

GeForce GTX 295		223776 MB/sec
Radeon HD 4870 2GB		115200 MB/sec
	Difference: 108576 (94%)

Texel Rate

The GeForce GTX 295 will be quite a bit (about 207%) more effective at anisotropic filtering than the Radeon HD 4870 2GB. (explain)

GeForce GTX 295		92160 Mtexels/sec
Radeon HD 4870 2GB		30000 Mtexels/sec
	Difference: 62160 (207%)

Pixel Rate

The GeForce GTX 295 will be quite a bit (more or less 169%) more effective at FSAA than the Radeon HD 4870 2GB, and also will be able to handle higher screen resolutions without losing too much performance. (explain)

GeForce GTX 295		32256 Mpixels/sec
Radeon HD 4870 2GB		12000 Mpixels/sec
	Difference: 20256 (169%)

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: Memory bandwidth is the maximum amount of information (counted in megabytes per second) that can be moved past the external memory interface within a second. It is calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This is worked out by multiplying the total number of texture units by the core clock 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 applied in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card can possibly write to its local memory in a second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill 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 max fill rate.