GeForce 8800 GTS (G80) 640MB vs GeForce GTS 250 512MB

Intro

Compare those specifications to the GeForce GTS 250 512MB, which comes with core speeds of 738 MHz on the GPU, and 1100 MHz on the 512 MB of GDDR3 RAM. It features 128 SPUs as well as 64 Texture Address Units and 16 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce 8800 GTS (G80) 640MB		143 Watts
GeForce GTS 250 512MB		145 Watts
	Difference: 2 Watts (1%)

Memory Bandwidth

The GeForce GTS 250 512MB should in theory perform a bit faster than the GeForce 8800 GTS (G80) 640MB overall. (explain)

GeForce GTS 250 512MB		70400 MB/sec
GeForce 8800 GTS (G80) 640MB		63360 MB/sec
	Difference: 7040 (11%)

Texel Rate

The GeForce GTS 250 512MB will be much (more or less 92%) more effective at texture filtering than the GeForce 8800 GTS (G80) 640MB. (explain)

GeForce GTS 250 512MB		47232 Mtexels/sec
GeForce 8800 GTS (G80) 640MB		24624 Mtexels/sec
	Difference: 22608 (92%)

Pixel Rate

If using a high screen resolution is important to you, then the GeForce GTS 250 512MB is superior to the GeForce 8800 GTS (G80) 640MB, though only just barely. (explain)

GeForce GTS 250 512MB		11808 Mpixels/sec
GeForce 8800 GTS (G80) 640MB		10260 Mpixels/sec
	Difference: 1548 (15%)

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 largest amount of information (in units of 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. If the card has DDR type RAM, it must be multiplied by 2 again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This figure is calculated by multiplying the total amount of texture units by the core speed of the chip. The better this number, 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 write to its local memory in a second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on many 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.