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Radeon HD 4850 1GB vs Radeon HD 4850 2GB
Intro
The Radeon HD 4850 1GB uses a 55 nm design. ATi has clocked the core frequency at 625 MHz. The GDDR4 RAM works at a frequency of 993 MHz on this model. It features 800(160x5) SPUs along with 40 Texture Address Units and 16 ROPs.Compare those specifications to the Radeon HD 4850 2GB, which has clock speeds of 625 MHz on the GPU, and 993 MHz on the 2048 MB of GDDR4 memory. It features 800(160x5) SPUs as well as 40 TAUs and 16 Rasterization Operator Units.
Power Usage and Theoretical Benchmarks
Both cards have the same power consumption.Memory Bandwidth
Both cards have exactly the same memory bandwidth, so in theory they should perform exactly the same. (explain)
Texel Rate
Both cards have exactly the same texel rate, so in theory they should perform equally good at at AF. (explain)Pixel Rate
Both cards have the exact same pixel rate, so theoretically they should be equally good at at full screen anti-aliasing, and be capable of handling the same resolutions. (explain)
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
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 4850 1GBAmazon.com
Other US-based stores
Amazon.co.uk
Amazon.de
Amazon.fr
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Radeon HD 4850 2GBAmazon.com
Other US-based stores
Amazon.co.uk
Amazon.de
Amazon.fr
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Specifications
| Model | Radeon HD 4850 1GB | Radeon HD 4850 2GB |
|---|---|---|
| Manufacturer | ATi | ATi |
| Year | Jun 25, 2008 | Jun 25, 2008 |
| Code Name | RV770 PRO | RV770 PRO |
| Fab Process | 55 nm | 55 nm |
| Bus | PCIe 2.0 x16 | PCIe 2.0 x16 |
| Memory | 1024 MB | 2048 MB |
| Core Speed | 625 MHz | 625 MHz |
| Shader Speed | N/A MHz | (N/A) MHz |
| Memory Speed | 993 MHz | 993 MHz |
| Unified Shaders | 800(160x5) | 800(160x5) |
| Texture Mapping Units | 40 | 40 |
| Render Output Units | 16 | 16 |
| Bus Type | GDDR4 | GDDR4 |
| Bus Width | 256-bit | 256-bit |
| DirectX Version | DirectX 10.1 | DirectX 10.1 |
| OpenGL Version | OpenGL 3.0 | OpenGL 3.0 |
| Power (Max TDP) | 110 watts | 110 watts |
| Shader Model | 4.1 | 4.1 |
| Bandwidth | 63552 MB/sec | 63552 MB/sec |
| Texel Rate | 25000 Mtexels/sec | 25000 Mtexels/sec |
| Pixel Rate | 10000 Mpixels/sec | 10000 Mpixels/sec |
Memory Bandwidth: Bandwidth is the maximum amount of information (in units of megabytes per second) that can be transported across the external memory interface in a second. It is worked out by multiplying the card's bus width by its memory clock speed. If it uses DDR memory, the result should be multiplied by 2 again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and high resolutions.
Texel Rate: Texel rate is the maximum number of texture map elements (texels) that can be applied per second. This is calculated by multiplying the total amount of texture units by the core clock speed of the chip. The higher the texel rate, the better the graphics 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 the video card could possibly record to the local memory per second - measured in millions of pixels per second. The number is calculated by multiplying the amount of Raster Operations Pipelines by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, especially the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the maximum fill rate.
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