GeForce 820M vs Radeon HD 4650 512MB

Intro

Compare all of that to the Radeon HD 4650 512MB, which features core speeds of 600 MHz on the GPU, and 500 MHz on the 512 MB of DDR2 RAM. It features 320(64x5) SPUs as well as 32 TAUs and 8 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 820M		15 Watts
Radeon HD 4650 512MB		55 Watts
	Difference: 40 Watts (267%)

Memory Bandwidth

Both cards have exactly the same bandwidth, so in theory they should have the same performance. (explain)

Texel Rate

The Radeon HD 4650 512MB is a lot (more or less 67%) more effective at texture filtering than the GeForce 820M. (explain)

Radeon HD 4650 512MB		19200 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 7696 (67%)

Pixel Rate

The Radeon HD 4650 512MB is quite a bit (more or less 67%) better at FSAA than the GeForce 820M, and also will be able to handle higher screen resolutions without slowing down too much. (explain)

Radeon HD 4650 512MB		4800 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 1924 (67%)

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 maximum amount of data (measured in MB per second) that can be moved over the external memory interface in one second. It's worked out by multiplying the bus width by its memory speed. In the case of DDR type RAM, it should be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied 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 graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the most pixels that the graphics card can possibly record to the local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the card's clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate also depends on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.