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Radeon HD 4850 1GB vs Radeon HD 7770
Intro
The Radeon HD 4850 1GB comes with a clock speed of 625 MHz and a GDDR4 memory speed of 993 MHz. It also makes use of a 256-bit memory bus, and uses a 55 nm design. It features 800(160x5) SPUs, 40 Texture Address Units, and 16 Raster Operation Units.Compare all of that to the Radeon HD 7770, which makes use of a 28 nm design. ATi has set the core speed at 1000 MHz. The GDDR5 RAM works at a speed of 1125 MHz on this particular card. It features 640 SPUs as well as 40 Texture Address Units and 16 ROPs.
Power Usage and Theoretical Benchmarks
Power Consumption (Max TDP)
| Radeon HD 7770 |
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80 Watts |
| Radeon HD 4850 1GB |
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110 Watts |
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Memory Bandwidth
The Radeon HD 7770 should in theory perform a bit faster than the Radeon HD 4850 1GB overall. (explain)
| Radeon HD 7770 |
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72000 MB/sec |
| Radeon HD 4850 1GB |
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63552 MB/sec |
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Texel Rate
The Radeon HD 7770 is quite a bit (about 60%) better at anisotropic filtering than the Radeon HD 4850 1GB. (explain)| Radeon HD 7770 |
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40000 Mtexels/sec |
| Radeon HD 4850 1GB |
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25000 Mtexels/sec |
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Pixel Rate
The Radeon HD 7770 is much (approximately 60%) more effective at anti-aliasing than the Radeon HD 4850 1GB, and also able to handle higher screen resolutions more effectively. (explain)| Radeon HD 7770 |
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16000 Mpixels/sec |
| Radeon HD 4850 1GB |
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10000 Mpixels/sec |
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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 7770Amazon.com
Other US-based stores
Amazon.co.uk
Amazon.de
Amazon.fr
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Specifications
| Model | Radeon HD 4850 1GB | Radeon HD 7770 |
|---|---|---|
| Manufacturer | ATi | ATi |
| Year | Jun 25, 2008 | February 2012 |
| Code Name | RV770 PRO | Cape Verde XT |
| Fab Process | 55 nm | 28 nm |
| Bus | PCIe 2.0 x16 | PCIe 3.0 x16 |
| Memory | 1024 MB | 1024 MB |
| Core Speed | 625 MHz | 1000 MHz |
| Shader Speed | N/A MHz | (N/A) MHz |
| Memory Speed | 993 MHz (1986 MHz effective) | 1125 MHz (4500 MHz effective) |
| Unified Shaders | 800(160x5) | 640 |
| Texture Mapping Units | 40 | 40 |
| Render Output Units | 16 | 16 |
| Bus Type | GDDR4 | GDDR5 |
| Bus Width | 256-bit | 128-bit |
| DirectX Version | DirectX 10.1 | DirectX 11.1 |
| OpenGL Version | OpenGL 3.0 | OpenGL 4.2 |
| Power (Max TDP) | 110 watts | 80 watts |
| Shader Model | 4.1 | 5.0 |
| Bandwidth | 63552 MB/sec | 72000 MB/sec |
| Texel Rate | 25000 Mtexels/sec | 40000 Mtexels/sec |
| Pixel Rate | 10000 Mpixels/sec | 16000 Mpixels/sec |
Memory Bandwidth: Memory bandwidth is the largest amount of information (measured in MB per second) that can be moved over the external memory interface in a second. The number is worked out by multiplying the interface width by the speed of its memory. If the card has DDR memory, it must be multiplied by 2 once again. If it uses DDR5, multiply by 4 instead. The better the bandwidth is, the better the card will be in general. It especially helps with AA, High Dynamic Range and higher screen resolutions.
Texel Rate: Texel rate is the maximum amount of texture map elements (texels) that are applied per second. This is worked out by multiplying the total amount 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 texture filtering (anisotropic filtering - AF). It is measured in millions of texels applied in one second.
Pixel Rate: Pixel rate is the most pixels the graphics card can possibly write to its local memory in a second - measured in millions of pixels per second. The number is worked out by multiplying the amount of colour ROPs by the clock speed of the card. ROPs (Raster Operations Pipelines - sometimes also referred to as Render Output Units) are responsible for filling the screen with pixels (the image). The actual pixel rate also depends on lots of other factors, most notably the memory bandwidth - the lower the memory bandwidth is, the lower the ability to get to the max fill rate.
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