GeForce GTX 650 vs Radeon HD 4850 512MB

Intro

Compare those specifications to the Radeon HD 4850 512MB, which makes use of a 55 nm design. AMD has set the core speed at 625 MHz. The GDDR3 RAM runs at a frequency of 993 MHz on this particular model. 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 4850 512MB		110 Watts
	Difference: 46 Watts (72%)

Memory Bandwidth

As far as performance goes, the GeForce GTX 650 should theoretically be much superior to the Radeon HD 4850 512MB in general. (explain)

GeForce GTX 650		80000 MB/sec
Radeon HD 4850 512MB		63552 MB/sec
	Difference: 16448 (26%)

Texel Rate

The GeForce GTX 650 will be much (approximately 35%) more effective at texture filtering than the Radeon HD 4850 512MB. (explain)

GeForce GTX 650		33856 Mtexels/sec
Radeon HD 4850 512MB		25000 Mtexels/sec
	Difference: 8856 (35%)

Pixel Rate

The GeForce GTX 650 is quite a bit (approximately 69%) more effective at full screen anti-aliasing than the Radeon HD 4850 512MB, and capable of handling higher screen resolutions while still performing well. (explain)

GeForce GTX 650		16928 Mpixels/sec
Radeon HD 4850 512MB		10000 Mpixels/sec
	Difference: 6928 (69%)

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 max amount of data (measured in megabytes per second) that can be transferred over the external memory interface within a second. The number is calculated by multiplying the card's bus width by the speed of its memory. In the case of DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the memory bandwidth, 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 number of texture map elements (texels) that can be processed per second. This figure is worked out by multiplying the total number of texture units by the core speed of the chip. The higher this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the most pixels that the graphics chip could possibly write to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the clock 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 fill rate is also dependant on quite a few other factors, most notably the memory bandwidth of the card - the lower the bandwidth is, the lower the ability to get to the maximum fill rate.