GeForce GTS 250 512MB vs GeForce GTS 450

Intro

Compare those specs to the GeForce GTS 450, which has core speeds of 783 MHz on the GPU, and 902 MHz on the 512 MB of GDDR5 memory. It features 192 SPUs as well as 32 Texture Address Units and 16 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTS 450		106 Watts
GeForce GTS 250 512MB		145 Watts
	Difference: 39 Watts (37%)

Memory Bandwidth

The GeForce GTS 250 512MB, in theory, should be a lot faster than the GeForce GTS 450 overall. (explain)

GeForce GTS 250 512MB		70400 MB/sec
GeForce GTS 450		57728 MB/sec
	Difference: 12672 (22%)

Texel Rate

The GeForce GTS 250 512MB will be quite a bit (about 89%) faster with regards to anisotropic filtering than the GeForce GTS 450. (explain)

GeForce GTS 250 512MB		47232 Mtexels/sec
GeForce GTS 450		25056 Mtexels/sec
	Difference: 22176 (89%)

Pixel Rate

The GeForce GTS 450 should be a bit (more or less 6%) more effective at anti-aliasing than the GeForce GTS 250 512MB, and will be able to handle higher resolutions more effectively. (explain)

GeForce GTS 450		12528 Mpixels/sec
GeForce GTS 250 512MB		11808 Mpixels/sec
	Difference: 720 (6%)

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 max amount of information (measured in megabytes per second) that can be transported across the external memory interface within a second. It's worked out by multiplying the bus width by its memory speed. If the card has DDR RAM, it must be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The better the card's 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 texture map elements (texels) that are applied per second. This number is worked out by multiplying the total texture units by the core speed of the chip. The higher this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied 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. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill 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 max fill rate.