GeForce 9800 GX2 vs Radeon HD 4850 512MB

Intro

The GeForce 9800 GX2 has a core clock speed of 600 MHz and a GDDR3 memory frequency of 1000 MHz. It also features a 256-bit bus, and uses a 65 nm design. It is comprised of 128 SPUs, 64 Texture Address Units, and 16 Raster Operation Units.

Compare those specs to the Radeon HD 4850 512MB, which uses a 55 nm design. ATi has set the core speed at 625 MHz. The GDDR3 RAM runs at a speed of 993 MHz on this particular model. It features 800(160x5) SPUs as well as 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.

GeForce 9800 GX2 Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Radeon HD 4850 512MB Amazon.com Other US-based stores Amazon.co.uk Amazon.de Amazon.fr

Specifications

Model	GeForce 9800 GX2	Radeon HD 4850 512MB
Manufacturer	nVidia	ATi
Year	Mar 2008	Jun 25, 2008
Code Name	G92	RV770 PRO
Fab Process	65 nm	55 nm
Bus	PCIe x16 2.0	PCIe 2.0 x16
Memory	512 MB (x2)	512 MB
Core Speed	600 MHz (x2)	625 MHz
Shader Speed	1500 MHz (x2)	(N/A) MHz
Memory Speed	1000 MHz (x2)	993 MHz
Unified Shaders	128 (x2)	800(160x5)
Texture Mapping Units	64 (x2)	40
Render Output Units	16 (x2)	16
Bus Type	GDDR3	GDDR3
Bus Width	256-bit (x2)	256-bit
DirectX Version	DirectX 10	DirectX 10.1
OpenGL Version	OpenGL 3.0	OpenGL 3.0
Power (Max TDP)	197 watts	110 watts
Shader Model	4.0	4.1
Bandwidth	128000 MB/sec	63552 MB/sec
Texel Rate	76800 Mtexels/sec	25000 Mtexels/sec
Pixel Rate	19200 Mpixels/sec	10000 Mpixels/sec

Memory Bandwidth: Bandwidth is the max amount of information (in units of MB per second) that can be transported over the external memory interface within a second. It is worked out by multiplying the card's bus width by the speed of its memory. In the case of DDR type RAM, 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 anti-aliasing, HDR and higher screen resolutions.

Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed per second. This figure is worked out by multiplying the total number of texture units of the card 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 applied per second.

Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to the local memory per second - measured in millions of pixels per second. The figure is calculated by multiplying the number of Render Output Units by the the core clock speed. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on many 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.