GeForce GTS 250 512MB vs Radeon HD 7770

Intro

Compare that to the Radeon HD 7770, which makes use of a 28 nm design. AMD has clocked the core frequency at 1000 MHz. The GDDR5 RAM works at a speed of 1125 MHz on this particular model. It features 640 SPUs as well as 40 TAUs and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7770		80 Watts
GeForce GTS 250 512MB		145 Watts
	Difference: 65 Watts (81%)

Memory Bandwidth

In theory, the Radeon HD 7770 should be a small bit faster than the GeForce GTS 250 512MB overall. (explain)

Radeon HD 7770		72000 MB/sec
GeForce GTS 250 512MB		70400 MB/sec
	Difference: 1600 (2%)

Texel Rate

The GeForce GTS 250 512MB is a bit (approximately 18%) more effective at texture filtering than the Radeon HD 7770. (explain)

GeForce GTS 250 512MB		47232 Mtexels/sec
Radeon HD 7770		40000 Mtexels/sec
	Difference: 7232 (18%)

Pixel Rate

If running with a high resolution is important to you, then the Radeon HD 7770 is superior to the GeForce GTS 250 512MB, by a large margin. (explain)

Radeon HD 7770		16000 Mpixels/sec
GeForce GTS 250 512MB		11808 Mpixels/sec
	Difference: 4192 (36%)

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 (in units of megabytes per second) that can be transferred over the external memory interface in a second. It is calculated by multiplying the bus width by the speed of its memory. If the card has DDR type RAM, the result should be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The higher the 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 per second. This figure is worked out by multiplying the total number of texture units of the card by the core clock speed of the chip. The better this number, the better the video card will be at texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip can possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount 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 output 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 get to the max fill rate.