Radeon HD 4770 vs Radeon HD 4830 1GB

Intro

Compare that to the Radeon HD 4830 1GB, which uses a 55 nm design. AMD has set the core frequency at 575 MHz. The GDDR4 RAM runs at a speed of 900 MHz on this particular model. It features 640(128x5) SPUs as well as 32 Texture Address Units and 16 ROPs.

Display Graphs

Hide Graphs

Power Usage and Theoretical Benchmarks

Power Consumption (Max TDP)

Radeon HD 4770		80 Watts
Radeon HD 4830 1GB		95 Watts
	Difference: 15 Watts (19%)

Memory Bandwidth

Theoretically speaking, the Radeon HD 4830 1GB should be a little bit faster than the Radeon HD 4770 in general. (explain)

Radeon HD 4830 1GB		57600 MB/sec
Radeon HD 4770		51200 MB/sec
	Difference: 6400 (13%)

Texel Rate

The Radeon HD 4770 will be a lot (about 30%) faster with regards to anisotropic filtering than the Radeon HD 4830 1GB. (explain)

Radeon HD 4770		24000 Mtexels/sec
Radeon HD 4830 1GB		18400 Mtexels/sec
	Difference: 5600 (30%)

Pixel Rate

The Radeon HD 4770 should be much (approximately 30%) faster with regards to AA than the Radeon HD 4830 1GB, and able to handle higher resolutions while still performing well. (explain)

Radeon HD 4770		12000 Mpixels/sec
Radeon HD 4830 1GB		9200 Mpixels/sec
	Difference: 2800 (30%)

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 information (in units of megabytes per second) that can be moved over the external memory interface in 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 DDR5, multiply by ANOTHER 2x. The better the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that can be applied per second. This is worked out by multiplying the total amount of texture units of the card by the core clock speed of the chip. The higher this number, the better the graphics card will be at handling texture filtering (anisotropic filtering - AF). It is measured in millions of texels processed in a second.

Pixel Rate: Pixel rate is the maximum number of pixels the video card could 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 Render Output Units 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 also depends on lots of other factors, especially the memory bandwidth of the card - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.