GeForce 820M vs GeForce GTS 250 512MB

Intro

Compare those specs to the GeForce GTS 250 512MB, which makes use of a 65/55 nm design. nVidia has set the core speed at 738 MHz. The GDDR3 RAM is set to run at a speed of 1100 MHz on this specific card. It features 128 SPUs along with 64 TAUs and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 820M		15 Watts
GeForce GTS 250 512MB		145 Watts
	Difference: 130 Watts (867%)

Memory Bandwidth

As far as performance goes, the GeForce GTS 250 512MB should in theory be a lot better than the GeForce 820M overall. (explain)

GeForce GTS 250 512MB		70400 MB/sec
GeForce 820M		16000 MB/sec
	Difference: 54400 (340%)

Texel Rate

The GeForce GTS 250 512MB will be a lot (about 311%) faster with regards to texture filtering than the GeForce 820M. (explain)

GeForce GTS 250 512MB		47232 Mtexels/sec
GeForce 820M		11504 Mtexels/sec
	Difference: 35728 (311%)

Pixel Rate

The GeForce GTS 250 512MB is a lot (approximately 311%) more effective at full screen anti-aliasing than the GeForce 820M, and capable of handling higher screen resolutions while still performing well. (explain)

GeForce GTS 250 512MB		11808 Mpixels/sec
GeForce 820M		2876 Mpixels/sec
	Difference: 8932 (311%)

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 (in units of MB per second) that can be transported across the external memory interface in one second. It is calculated by multiplying the bus width by the speed of its memory. If it uses DDR memory, it should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that can be 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 higher the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the amount of ROPs by the the core clock speed. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate is also dependant on quite a few 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.