Radeon HD 4770 vs Radeon R9 M390X

Intro

Compare those specs to the Radeon R9 M390X, which has a core clock speed of 723 MHz and a GDDR5 memory frequency of 1250 MHz. It also uses a 256-bit bus, and makes use of a 28 nm design. It is comprised of 2048 SPUs, 128 Texture Address Units, and 32 Raster Operation Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4770		80 Watts
Radeon R9 M390X		125 Watts
	Difference: 45 Watts (56%)

Memory Bandwidth

The Radeon R9 M390X should in theory be quite a bit faster than the Radeon HD 4770 overall. (explain)

Radeon R9 M390X		160000 MB/sec
Radeon HD 4770		51200 MB/sec
	Difference: 108800 (213%)

Texel Rate

The Radeon R9 M390X will be a lot (about 286%) better at texture filtering than the Radeon HD 4770. (explain)

Radeon R9 M390X		92544 Mtexels/sec
Radeon HD 4770		24000 Mtexels/sec
	Difference: 68544 (286%)

Pixel Rate

If running with high levels of AA is important to you, then the Radeon R9 M390X is the winner, by far. (explain)

Radeon R9 M390X		23136 Mpixels/sec
Radeon HD 4770		12000 Mpixels/sec
	Difference: 11136 (93%)

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 data (counted in MB per second) that can be moved over the external memory interface within a second. The number is worked out by multiplying the card's interface width by the speed of its memory. In the case of DDR RAM, it should be multiplied by 2 once again. If it uses DDR5, multiply by ANOTHER 2x. 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 number of texture map elements (texels) that can be processed in one second. This figure is calculated by multiplying the total texture units by the core speed of the chip. The higher the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels per second.

Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is calculated by multiplying the number of colour ROPs by the the core speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate also depends on quite a few other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the potential to get to the max fill rate.