Radeon HD 7870 vs Radeon R9 M290X

Intro

Compare all of that to the Radeon R9 M290X, which features clock speeds of 850 MHz on the GPU, and 1200 MHz on the 4096 MB of GDDR5 RAM. It features 1280 SPUs along with 80 Texture Address Units and 32 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon R9 M290X		100 Watts
Radeon HD 7870		175 Watts
	Difference: 75 Watts (75%)

Memory Bandwidth

Both cards have exactly the same memory bandwidth, so theoretically they should perform the same. (explain)

Texel Rate

The Radeon HD 7870 will be a little bit (about 18%) faster with regards to AF than the Radeon R9 M290X. (explain)

Radeon HD 7870		80000 Mtexels/sec
Radeon R9 M290X		68000 Mtexels/sec
	Difference: 12000 (18%)

Pixel Rate

The Radeon HD 7870 should be a little bit (about 18%) more effective at AA than the Radeon R9 M290X, and also able to handle higher resolutions without slowing down too much. (explain)

Radeon HD 7870		32000 Mpixels/sec
Radeon R9 M290X		27200 Mpixels/sec
	Difference: 4800 (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: Memory bandwidth is the maximum amount of data (counted in megabytes per second) that can be transferred past the external memory interface within a second. The number is calculated by multiplying the bus width by the speed of its memory. If the card has DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. The higher the card's memory bandwidth, 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 processed in one second. This is calculated by multiplying the total number of texture units by the core 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 applied in a second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics chip could possibly record to the local memory in a second - measured in millions of pixels per second. The figure is worked out by multiplying the number of colour ROPs by the the card's clock speed. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for drawing the pixels (image) on the screen. The actual pixel output rate is also dependant on many other factors, most notably the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.