With the impending release of DirectX 12 just around the corner, Windows 10 being released, VR technology, the Vulkan API, and many other fascinating releases it is an amazing time to be a PC gamer. AMD is currently three years into their GCN architecture at this point, but certain features that the chips have had for a while are only coming into their own. This is down to the improvements by the next-generation of APIs.
Currently the Asynchronous Command Engine (ACEs) that are part of every GCN-class video card is proving this point. The HD 7900 group had two ACE’s per GPU, while AMD’s Hawaii-class hardware has pushed this up to eight. This is also confirmed in the PS4 and possibly the Xbox One. AMD’s Graphics Core Next (GCN) GPUs are capable of asynchronous execution to some degree, as can the Nvidia GPUs based on the GTX 900 “Maxwell” group.
What is an Asynchronous Command Engine I hear you ask? The ACE units inside the AMD’s GCN architecture are based simply for flexibility. Basically instead of being forced to execute a single queue via pre-determined order, even when it makes no sense to do so, tasks from different queues can be scheduled and completed independently. So this lets the GPU to execute some tasks out of sync if they want to. If the GPU knows that a time-sensitive operation that only needs 10ns of compute time is in the queue alongside a long memory copy that isn’t particularly needed, it can make the short task and complete it, then it moves over to the long task again.
What it means is that the point of ACE’s is that they allow the GPU to process and execute multiple command streams in parallel. The last version of DirectX11 didn’t have this possibility. Which means that in principal it has no way to tell the graphics and compute into the same workload. So really AMD have built Kaveri and the SoCs for the PS4 and Xbox One, it includes eight ACEs in those chips as well. It lets programmers use the GPU’s horsepower more effectively. This will enable the physics and certain other types of in-game calculations to be handled in the background.
So what does this mean for us? It means that the DX12 and Vulkan are now challenging and reinventing 3D APIs. The new capabilities are going to improve everything including multi-GPU to VR Displays. Bringing in 4K monitors, FreeSync, G-Sync support it is an extremely exciting time for the whole of the PC gaming industry.
Guess I picked the right time to get into PC gaming.