GeForce 820M vs GeForce 8800 Ultra

Intro

Compare that to the GeForce 8800 Ultra, which comes with GPU clock speed of 612 MHz, and 768 MB of GDDR3 memory set to run at 1080 MHz through a 384-bit bus. It also features 128 Stream Processors, 64 Texture Address Units, and 24 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 820M		15 Watts
GeForce 8800 Ultra		171 Watts
	Difference: 156 Watts (1040%)

Memory Bandwidth

The GeForce 8800 Ultra should in theory be a lot faster than the GeForce 820M overall. (explain)

GeForce 8800 Ultra		103680 MB/sec
GeForce 820M		16000 MB/sec
	Difference: 87680 (548%)

Texel Rate

The GeForce 8800 Ultra is quite a bit (more or less 240%) more effective at AF than the GeForce 820M. (explain)

GeForce 8800 Ultra		39168 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 27664 (240%)

Pixel Rate

The GeForce 8800 Ultra should be quite a bit (more or less 411%) faster with regards to full screen anti-aliasing than the GeForce 820M, and capable of handling higher resolutions better. (explain)

GeForce 8800 Ultra		14688 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 11812 (411%)

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 maximum amount of data (measured in megabytes per second) that can be moved across the external memory interface in one second. It's calculated by multiplying the card's bus width by its memory speed. If it uses DDR type memory, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are applied in one second. This is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in a second.

Pixel Rate: Pixel rate is the maximum number of pixels the graphics 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 Render Output Units by the the card's clock speed. 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 also depends on many other factors, especially the memory bandwidth of the card - the lower the bandwidth is, the lower the potential to get to the maximum fill rate.