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Radeon HD 4890 1GB vs Radeon HD 4890 2GB
Intro
The Radeon HD 4890 1GB has a GPU clock speed of 1000 MHz, and the 1024 MB of GDDR5 memory runs at 975 MHz through a 256-bit bus. It also is comprised of 800(160x5) SPUs, 40 Texture Address Units, and 16 ROPs.Compare those specs to the Radeon HD 4890 2GB, which comes with GPU clock speed of 1000 MHz, and 2048 MB of GDDR5 RAM set to run at 975 MHz through a 256-bit bus. It also is comprised of 800(160x5) SPUs, 40 TAUs, 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 memory bandwidth, so theoretically they should perform exactly the same. (explain)
Texel Rate
Both cards have the exact same texel fill rate, so theoretically they should perform equally good at at AF. (explain)Pixel Rate
Both cards have exactly the same pixel rate, so theoretically they should perform equally good at at AA, and be able to handle the same screen 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
Radeon HD 4890 1GBAmazon.com
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Radeon HD 4890 2GBAmazon.com
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Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
Specifications
| Model | Radeon HD 4890 1GB | Radeon HD 4890 2GB |
|---|---|---|
| Manufacturer | AMD | AMD |
| Year | Apr 2, 2009 | Apr 2, 2009 |
| Code Name | RV790 XT | RV790 XT |
| Memory | 1024 MB | 2048 MB |
| Core Speed | 1000 MHz | 1000 MHz |
| Memory Speed | 3900 MHz | 3900 MHz |
| Power (Max TDP) | 190 watts | 190 watts |
| Bandwidth | 124800 MB/sec | 124800 MB/sec |
| Texel Rate | 40000 Mtexels/sec | 40000 Mtexels/sec |
| Pixel Rate | 16000 Mpixels/sec | 16000 Mpixels/sec |
| Unified Shaders | 800(160x5) | 800(160x5) |
| Texture Mapping Units | 40 | 40 |
| Render Output Units | 16 | 16 |
| Bus Type | GDDR5 | GDDR5 |
| Bus Width | 256-bit | 256-bit |
| Fab Process | 55 nm | 55 nm |
| Transistors | 959 million | 959 million |
| Bus | PCIe 2.0 x16 | PCIe 2.0 x16 |
| DirectX Version | DirectX 10.1 | DirectX 10.1 |
| OpenGL Version | OpenGL 3.0 | OpenGL 3.0 |
Memory Bandwidth: Bandwidth is the max amount of data (measured in MB per second) that can be transported over the external memory interface within a second. It is calculated by multiplying the bus width by its memory speed. If the card has DDR type memory, it should be multiplied by 2 again. If DDR5, multiply by 4 instead. The higher the card's memory bandwidth, the faster the card will be in general. It especially helps with AA, HDR and higher screen resolutions.
Texel Rate: Texel rate is the maximum texture map elements (texels) that can be applied in one second. This number is calculated by multiplying the total texture units 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 processed per second.
Pixel Rate: Pixel rate is the maximum number of pixels that the graphics chip could possibly write to its local memory per second - measured in millions of pixels per second. Pixel rate is worked out by multiplying the number of Render Output Units by the clock speed of the card. ROPs (Raster Operations Pipelines - aka Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel fill rate is also dependant on many other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the potential to reach the max fill rate.
Radeon HD 4890 1GBAmazon.com
Check prices at:
|
Radeon HD 4890 2GBAmazon.com
Check prices at:
|
Please note that the price comparisons are based on search keywords - sometimes it might show cards with very similar names that are not exactly the same as the one chosen in the comparison. We do try to filter out the wrong results as best we can, though.
|
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