GeForce GTX 650 vs Radeon HD 3870 1GB

Intro

Compare those specifications to the Radeon HD 3870 1GB, which uses a 55 nm design. AMD has clocked the core speed at 775 MHz. The GDDR4 memory works at a frequency of 1125 MHz on this card. It features 320(64x5) SPUs as well as 16 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 650		64 Watts
Radeon HD 3870 1GB		106 Watts
	Difference: 42 Watts (66%)

Memory Bandwidth

As far as performance goes, the GeForce GTX 650 should in theory be a bit better than the Radeon HD 3870 1GB in general. (explain)

GeForce GTX 650		80000 MB/sec
Radeon HD 3870 1GB		72000 MB/sec
	Difference: 8000 (11%)

Texel Rate

The GeForce GTX 650 should be much (more or less 173%) more effective at anisotropic filtering than the Radeon HD 3870 1GB. (explain)

GeForce GTX 650		33856 Mtexels/sec
Radeon HD 3870 1GB		12400 Mtexels/sec
	Difference: 21456 (173%)

Pixel Rate

If using a high screen resolution is important to you, then the GeForce GTX 650 is a better choice, by a large margin. (explain)

GeForce GTX 650		16928 Mpixels/sec
Radeon HD 3870 1GB		12400 Mpixels/sec
	Difference: 4528 (37%)

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: Memory bandwidth is the max amount of data (in units of megabytes per second) that can be moved over the external memory interface within a second. It is calculated by multiplying the interface width by its memory speed. If the card has DDR type memory, the result 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 AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed per second. This is calculated by multiplying the total texture units of the card by the core clock speed of the chip. The better the texel rate, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a 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 core speed of the card. 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 output rate is also dependant on lots of other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.