GeForce GTS 450 1GB vs Radeon HD 4850 512MB

Intro

Compare that to the Radeon HD 4850 512MB, which makes use of a 55 nm design. ATi has set the core speed at 625 MHz. The GDDR3 memory runs at a frequency of 993 MHz on this particular card. It features 800(160x5) SPUs as well as 40 TAUs and 16 ROPs.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTS 450 1GB		106 Watts
Radeon HD 4850 512MB		110 Watts
	Difference: 4 Watts (4%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 4850 512MB is 10% faster than the GeForce GTS 450 1GB in general, due to its greater data rate. (explain)

Radeon HD 4850 512MB		63552 MB/sec
GeForce GTS 450 1GB		57728 MB/sec
	Difference: 5824 (10%)

Texel Rate

The GeForce GTS 450 1GB should be a small bit (more or less 0%) more effective at anisotropic filtering than the Radeon HD 4850 512MB. (explain)

GeForce GTS 450 1GB		25056 Mtexels/sec
Radeon HD 4850 512MB		25000 Mtexels/sec
	Difference: 56 (0%)

Pixel Rate

The GeForce GTS 450 1GB is much (approximately 25%) faster with regards to AA than the Radeon HD 4850 512MB, and should be capable of handling higher screen resolutions better. (explain)

GeForce GTS 450 1GB		12528 Mpixels/sec
Radeon HD 4850 512MB		10000 Mpixels/sec
	Difference: 2528 (25%)

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 maximum amount of data (counted in MB per second) that can be moved across the external memory interface in a second. It's worked out by multiplying the bus width by its memory speed. If it uses DDR RAM, it should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, the faster 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 number of texture map elements (texels) that are processed per second. This number is calculated by multiplying the total number of texture units by the core speed of the chip. The better this number, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed per second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip 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 amount of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on quite a few other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to get to the maximum fill rate.