GeForce GTS 250 1GB vs Radeon HD 4850 1GB

Intro

Compare those specs to the Radeon HD 4850 1GB, which has a clock frequency of 625 MHz and a GDDR4 memory speed of 993 MHz. It also makes use of a 256-bit bus, and uses a 55 nm design. It features 800(160x5) SPUs, 40 TAUs, and 16 Raster Operation Units.

(No game benchmarks for this combination yet.)

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4850 1GB		110 Watts
GeForce GTS 250 1GB		145 Watts
	Difference: 35 Watts (32%)

Memory Bandwidth

Performance-wise, the GeForce GTS 250 1GB should theoretically be a little bit better than the Radeon HD 4850 1GB overall. (explain)

GeForce GTS 250 1GB		70400 MB/sec
Radeon HD 4850 1GB		63552 MB/sec
	Difference: 6848 (11%)

Texel Rate

The GeForce GTS 250 1GB should be quite a bit (about 89%) more effective at anisotropic filtering than the Radeon HD 4850 1GB. (explain)

GeForce GTS 250 1GB		47232 Mtexels/sec
Radeon HD 4850 1GB		25000 Mtexels/sec
	Difference: 22232 (89%)

Pixel Rate

The GeForce GTS 250 1GB is a bit (about 18%) better at AA than the Radeon HD 4850 1GB, and also will be able to handle higher resolutions without slowing down too much. (explain)

GeForce GTS 250 1GB		11808 Mpixels/sec
Radeon HD 4850 1GB		10000 Mpixels/sec
	Difference: 1808 (18%)

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 largest amount of information (in units of MB per second) that can be transferred over the external memory interface within a second. It is calculated by multiplying the card's bus width by the speed of its memory. If it uses DDR type RAM, it should 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, HDR and high resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied in one second. This figure is calculated by multiplying the total number 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 applied in a second.

Pixel Rate: Pixel rate is the most pixels the video card can possibly record to its local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Render Output Units 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 fill rate is also dependant on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.