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

Intro

Compare that to the Radeon R9 390X 8G, which comes with a clock speed of 1050 MHz and a GDDR5 memory frequency of 1500 MHz. It also features a 512-bit memory bus, and makes use of a 28 nm design. It features 2816 SPUs, 176 Texture Address Units, and 64 Raster Operation 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

As far as performance goes, the Radeon R9 390X 8G should in theory be quite a bit better than the Radeon R7 250X 2GB overall. (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 will be a lot (about 362%) faster with regards to 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

If running with a high screen resolution is important to you, then the Radeon R9 390X 8G is superior to the Radeon R7 250X 2GB, and very much so. (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: Bandwidth is the maximum amount of information (measured in megabytes per second) that can be transported across the external memory interface in one second. The number is calculated by multiplying the interface width by its memory speed. If the card has DDR memory, it should be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The higher the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are applied per second. This figure is worked out by multiplying the total number of texture units by the core speed of the chip. The higher 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 card can possibly record to the local memory in a second - measured in millions of pixels per second. The number is calculated by multiplying the number of colour ROPs by the clock speed of the card. 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 rate is also dependant on many other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.