Radeon HD 4890 1GB vs Radeon HD 7750

Intro

Compare that to the Radeon HD 7750, which makes use of a 28 nm design. AMD has set the core speed at 800 MHz. The GDDR5 RAM is set to run at a frequency of 1125 MHz on this specific card. It features 512 SPUs along with 32 Texture Address Units and 16 Rasterization Operator Units.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 7750		55 Watts
Radeon HD 4890 1GB		190 Watts
	Difference: 135 Watts (245%)

Memory Bandwidth

Theoretically, the Radeon HD 4890 1GB should be a lot faster than the Radeon HD 7750 in general. (explain)

Radeon HD 4890 1GB		124800 MB/sec
Radeon HD 7750		72000 MB/sec
	Difference: 52800 (73%)

Texel Rate

The Radeon HD 4890 1GB should be quite a bit (more or less 56%) more effective at anisotropic filtering than the Radeon HD 7750. (explain)

Radeon HD 4890 1GB		40000 Mtexels/sec
Radeon HD 7750		25600 Mtexels/sec
	Difference: 14400 (56%)

Pixel Rate

If using a high screen resolution is important to you, then the Radeon HD 4890 1GB is a better choice, by far. (explain)

Radeon HD 4890 1GB		16000 Mpixels/sec
Radeon HD 7750		12800 Mpixels/sec
	Difference: 3200 (25%)

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 data (counted in MB per second) that can be moved across the external memory interface in a second. It's calculated by multiplying the card's interface width by its memory speed. If the card has DDR memory, it must be multiplied by 2 again. If DDR5, multiply by 4 instead. The better the card's memory bandwidth, the better the card will be in general. It especially helps with AA, High Dynamic Range and high resolutions.

Texel Rate: Texel rate is the maximum texture map elements (texels) that are processed in one second. This is worked out by multiplying the total texture units by the core clock speed of the chip. The better the texel rate, the better the card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels in one second.

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card can possibly write to its local memory in a second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Raster Operations Pipelines by the the core speed of the card. ROPs (Raster Operations Pipelines - also called Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel output rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to reach the max fill rate.