Radeon R7 250X 2GB vs Radeon R9 390X 8G

Intro

Compare that to the Radeon R9 390X 8G, which features clock speeds of 1050 MHz on the GPU, and 1500 MHz on the 8192 MB of GDDR5 memory. It features 2816 SPUs as well as 176 TAUs and 64 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R7 250X 2GB		95 Watts
Radeon R9 390X 8G		275 Watts
	Difference: 180 Watts (189%)

Memory Bandwidth

The Radeon R9 390X 8G should in theory perform quite a bit faster than the Radeon R7 250X 2GB in general. (explain)

Radeon R9 390X 8G		384000 MB/sec
Radeon R7 250X 2GB		72000 MB/sec
	Difference: 312000 (433%)

Texel Rate

The Radeon R9 390X 8G should be much (about 362%) more effective at AF than the Radeon R7 250X 2GB. (explain)

Radeon R9 390X 8G		184800 Mtexels/sec
Radeon R7 250X 2GB		40000 Mtexels/sec
	Difference: 144800 (362%)

Pixel Rate

The Radeon R9 390X 8G is quite a bit (approximately 320%) more effective at AA than the Radeon R7 250X 2GB, and should be capable of handling higher screen resolutions while still performing well. (explain)

Radeon R9 390X 8G		67200 Mpixels/sec
Radeon R7 250X 2GB		16000 Mpixels/sec
	Difference: 51200 (320%)

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 (in units of megabytes per second) that can be transferred over the external memory interface in a second. The number is calculated by multiplying the card's bus width by its memory clock speed. In the case of DDR RAM, the result should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the faster the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be processed per second. This number is calculated by multiplying the total amount of texture units of the card by the core clock 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 amount of pixels the graphics card can possibly record to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for drawing the pixels (image) on 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 maximum fill rate.