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Radeon HD 4850 1GB vs Radeon HD 4850 512MB
Intro
The Radeon HD 4850 1GB uses a 55 nm design. ATi has set the core frequency at 625 MHz. The GDDR4 memory runs at a speed of 993 MHz on this specific model. It features 800(160x5) SPUs along with 40 TAUs and 16 Rasterization Operator Units.Compare those specifications to the Radeon HD 4850 512MB, which features GPU core speed of 625 MHz, and 512 MB of GDDR3 memory set to run at 993 MHz through a 256-bit bus. It also is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.
Power Usage and Theoretical Benchmarks
Both cards have the same power consumption.Memory Bandwidth
Both cards have exactly the same bandwidth, so theoretically they should perform exactly the same. (explain)
Texel Rate
Both cards have the exact same texel fill rate, so in theory they should perform equally good at at anisotropic filtering. (explain)Pixel Rate
Both cards have exactly the same pixel fill rate, so theoretically they should perform 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 512MBAmazon.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 512MB |
|---|---|---|
| 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 | 512 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 | GDDR3 |
| 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 (counted in megabytes per second) that can be moved across the external memory interface in one second. It is calculated by multiplying the bus width by its memory speed. In the case of DDR type RAM, it must be multiplied by 2 once again. If DDR5, multiply by ANOTHER 2x. The better the card's memory bandwidth, the better the card will be in general. It especially helps with anti-aliasing, High Dynamic Range and high resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are processed in one second. This is worked out by multiplying the total texture units by the core speed of the chip. The better the texel rate, the better the video 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 graphics card could possibly record to its local memory per second - measured in millions of pixels per second. The figure is worked out by multiplying the number 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 outputting the pixels (image) to the screen. The actual pixel fill rate is also dependant on lots of other factors, most notably the memory bandwidth - the lower the bandwidth is, the lower the ability to get to the max fill rate.
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