GeForce GT 315 vs Radeon HD 4870 X2

Intro

Compare all that to the Radeon HD 4870 X2, which uses a 55 nm design. AMD has clocked the core speed at 750 MHz. The GDDR5 RAM works at a frequency of 900 MHz on this model. It features 800(160x5) SPUs as well as 40 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GT 315		52 Watts
Radeon HD 4870 X2		350 Watts
	Difference: 298 Watts (573%)

Memory Bandwidth

As far as performance goes, the Radeon HD 4870 X2 should in theory be quite a bit better than the GeForce GT 315 overall. (explain)

Radeon HD 4870 X2		230400 MB/sec
GeForce GT 315		25280 MB/sec
	Difference: 205120 (811%)

Texel Rate

The Radeon HD 4870 X2 is a lot (about 500%) more effective at texture filtering than the GeForce GT 315. (explain)

Radeon HD 4870 X2		60000 Mtexels/sec
GeForce GT 315		10000 Mtexels/sec
	Difference: 50000 (500%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon HD 4870 X2 is superior to the GeForce GT 315, by far. (explain)

Radeon HD 4870 X2		24000 Mpixels/sec
GeForce GT 315		5000 Mpixels/sec
	Difference: 19000 (380%)

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 largest amount of information (counted in MB per second) that can be transferred over the external memory interface in a second. The number is calculated by multiplying the card's interface width by the speed of its memory. If the card has DDR type memory, it should be multiplied by 2 once again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the faster the card will be in general. It especially helps with anti-aliasing, HDR 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 texture units of the card by the core speed of the chip. The better this number, the better the card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip can possibly record to its local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the amount of Raster Operations Pipelines by the the card's clock speed. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the max fill rate.