GeForce GTX 650 vs Radeon HD 4870 2GB

Intro

Compare all of that to the Radeon HD 4870 2GB, which uses a 55 nm design. AMD has set the core frequency at 750 MHz. The GDDR5 RAM works at a frequency of 900 MHz on this specific card. It features 800(160x5) SPUs as well as 40 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 4870 2GB		150 Watts
	Difference: 86 Watts (134%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 4870 2GB is 44% faster than the GeForce GTX 650 overall, due to its greater data rate. (explain)

Radeon HD 4870 2GB		115200 MB/sec
GeForce GTX 650		80000 MB/sec
	Difference: 35200 (44%)

Texel Rate

The GeForce GTX 650 should be a small bit (more or less 13%) faster with regards to AF than the Radeon HD 4870 2GB. (explain)

GeForce GTX 650		33856 Mtexels/sec
Radeon HD 4870 2GB		30000 Mtexels/sec
	Difference: 3856 (13%)

Pixel Rate

If running with high levels of AA is important to you, then the GeForce GTX 650 is a better choice, and very much so. (explain)

GeForce GTX 650		16928 Mpixels/sec
Radeon HD 4870 2GB		12000 Mpixels/sec
	Difference: 4928 (41%)

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 (measured in megabytes per second) that can be transported over the external memory interface in a second. The number is worked out by multiplying the card's bus width by the speed of its memory. If the card has DDR RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, 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 amount of texture map elements (texels) that are processed in one second. This figure is worked out by multiplying the total texture units of the card by the core speed of the chip. The better the texel rate, the better the video card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels the video card could possibly record to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of ROPs 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 lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.