AMD RX Vega – What is Rapid Packed Math?

AMD RX Vega - What is Rapid Packed Math?

AMD RX Vega – What is Rapid Packed Math?

One of Vega’s key features is Rapid Packed Math technology, which allows 16-bit operations to be used between 32-bit operating, effectively enabling mixed-compute workloads. 
Now all calculations need the same level of precision for accurate results, so if mixed precision is available and 16-bit operations can be calculated at a faster rate developers could utilise 16-bit operations to deliver enhanced performance with no visual downsides. 

This will allow developers to conduct certain calculations faster, allowing frames to be completed at a faster rate and increase the framerate and responsiveness of future gaming titles. 

What needs to be noted here is that not all in-game calculations can be used with Rapid Packed Math, so don’t expect a 2x performance increase in games that can utilise it. The performance impact of this technology will depend on how much game code can be simplified with rapid packed math, which is a factor that will no doubt change on a game by game basis, and how much time developers are willing to spend on a feature that not all graphics cards support. 


AMD RX Vega - What is Rapid Packed Math?AMD RX Vega - What is Rapid Packed Math?


If you are thinking that developers won’t support this feature you would be wrong, with the development team behind Far Cry 5 already confirming that they will be making use of the feature. The PS4 Pro also supports 16-bit mixed precision, giving developers more reason to create games with this feature in mind. 

AMD has also been working with Futuremark to create a benchmark that will showcase the potential of Rapid Packed Math, already showing a 25% gain in operation count in certain tasks. At this time it is unknown if 3DMARK Serra will ever be released to the public. 

one other key aspect of this feature is that Mixed Precision is supported by DirectX 12 and Vulkan, which means that gamers will not need to wait for a standards change before the feature can be used.  

AMD RX Vega - What is Rapid Packed Math?  

At the time of writing it is unknown how much of a performance impact Rapid Packed Math will have in games, though some will no doubt see it as an Async-Compute-like feature that will deliver “free/extra performance” in games that support it.   

With AMD’s new Vega architecture supporting this feature alongside the PS4 Pro there is no doubt that developers will make use of this feature, though like Async Compute it will likely not be widely adopted for quite some time. 


You can join the discussion on Vega’s support for Rapid Packed Math on the OC3D Forums.