GeForce GTX 275 vs Radeon R9 390 8G

Intro

Compare those specifications to the Radeon R9 390 8G, which features a clock speed of 1000 MHz and a GDDR5 memory speed of 1500 MHz. It also makes use of a 512-bit memory bus, and uses a 28 nm design. It is made up of 2560 SPUs, 160 Texture Address Units, and 64 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

GeForce GTX 275		219 Watts
Radeon R9 390 8G		275 Watts
	Difference: 56 Watts (26%)

Memory Bandwidth

The Radeon R9 390 8G should theoretically perform a lot faster than the GeForce GTX 275 overall. (explain)

Radeon R9 390 8G		384000 MB/sec
GeForce GTX 275		127008 MB/sec
	Difference: 256992 (202%)

Texel Rate

The Radeon R9 390 8G will be a lot (more or less 216%) better at AF than the GeForce GTX 275. (explain)

Radeon R9 390 8G		160000 Mtexels/sec
GeForce GTX 275		50640 Mtexels/sec
	Difference: 109360 (216%)

Pixel Rate

The Radeon R9 390 8G should be quite a bit (about 261%) faster with regards to FSAA than the GeForce GTX 275, and also capable of handling higher resolutions without slowing down too much. (explain)

Radeon R9 390 8G		64000 Mpixels/sec
GeForce GTX 275		17724 Mpixels/sec
	Difference: 46276 (261%)

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 transported past the external memory interface within a second. It is calculated by multiplying the card's interface width by its memory clock speed. If the card has DDR type memory, it must be multiplied by 2 again. If it uses DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that are processed in one second. This is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the graphics 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 most pixels the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the amount 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 is also dependant on lots of other factors, especially the memory bandwidth - the lower the bandwidth is, the lower the ability to reach the maximum fill rate.