Radeon HD 4830 512MB vs Radeon HD 6770

Intro

The Radeon HD 4830 512MB features a core clock speed of 575 MHz and a GDDR3 memory speed of 900 MHz. It also makes use of a 256-bit memory bus, and makes use of a 55 nm design. It is made up of 640(128x5) SPUs, 32 TAUs, and 16 Raster Operation Units.

Compare those specs to the Radeon HD 6770, which makes use of a 40 nm design. ATi has set the core speed at 900 MHz. The GDDR5 memory runs at a frequency of 1050 MHz on this card. It features 800 SPUs along with 40 Texture Address Units and 16 ROPs.

Price Comparison

Please note that the price comparisons are based on search keywords, and might not be the exact same card listed on this page. We have no control over the accuracy of their search results.

Radeon HD 4830 512MB Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Radeon HD 6770 Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Specifications

Model	Radeon HD 4830 512MB	Radeon HD 6770
Manufacturer	ATi	ATi
Year	Oct 21, 2008	January 2011
Code Name	RV770 LE	Juniper XT
Fab Process	55 nm	40 nm
Bus	PCIe 2.0 x16	PCIe x16
Memory	512 MB	512 MB
Core Speed	575 MHz	900 MHz
Shader Speed	N/A MHz	(N/A) MHz
Memory Speed	900 MHz	1050 MHz
Unified Shaders	640(128x5)	800
Texture Mapping Units	32	40
Render Output Units	16	16
Bus Type	GDDR3	GDDR5
Bus Width	256-bit	128-bit
DirectX Version	DirectX 10.1	DirectX 11
OpenGL Version	OpenGL 3.0	OpenGL 4.1
Power (Max TDP)	95 watts	108 watts
Shader Model	4.1	5.0
Bandwidth	57600 MB/sec	67200 MB/sec
Texel Rate	18400 Mtexels/sec	36000 Mtexels/sec
Pixel Rate	9200 Mpixels/sec	14400 Mpixels/sec

Memory Bandwidth: Memory bandwidth is the max amount of data (counted in megabytes per second) that can be moved over the external memory interface in a second. It is worked out by multiplying the interface width by its memory clock speed. In the case of DDR type memory, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The higher the memory bandwidth, the better the card will be in general. It especially helps with AA, HDR and high resolutions.

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

Pixel Rate: Pixel rate is the maximum amount of pixels that the graphics card could possibly record to the local memory in one second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the amount of Render Output Units by the the core speed of the card. ROPs (Raster Operations Pipelines - also sometimes called 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 of the card - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.