GeForce 820M vs GeForce GT 310

Intro

Compare all of that to the GeForce GT 310, which uses a 40 nm design. nVidia has clocked the core speed at 589 MHz. The DDR2 memory works at a speed of 1000 MHz on this card. It features 16 SPUs as well as 8 TAUs and 4 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 820M		15 Watts
GeForce GT 310		31 Watts
	Difference: 16 Watts (107%)

Memory Bandwidth

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

Texel Rate

The GeForce 820M is quite a bit (more or less 144%) better at AF than the GeForce GT 310. (explain)

GeForce 820M		11504 Mtexels/sec
GeForce GT 310		4712 Mtexels/sec
	Difference: 6792 (144%)

Pixel Rate

The GeForce 820M will be a lot (approximately 22%) better at FSAA than the GeForce GT 310, and also able to handle higher resolutions without slowing down too much. (explain)

GeForce 820M		2876 Mpixels/sec
GeForce GT 310		2356 Mpixels/sec
	Difference: 520 (22%)

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 information (in units of MB per second) that can be transported across the external memory interface within a second. It's worked out by multiplying the interface width by its memory speed. If the card has DDR RAM, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels the graphics card can possibly record to its local memory in one second - measured in millions of pixels per second. The figure is worked out by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel fill rate is also dependant on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.