Xbox 720 will be coming to retailers most likely at the end of this year, but some news completely dissecting its GPU has surfaced, which may provide gamers with a deeper understanding of the system.
According to a report from VGLeaks yesterday, the Xbox 720 apparently will include a handful of fixed-function accelerators, where a group of move engines are one of them.
Xbox 720 apparently has four move engines itself which allows for fast direct memory access to take place.
The algorithms for the move engines are embedded in the hardware, and they are looked at as black boxes that have zero intermediate results relating to the system's software.
Their true purpose is to take workloads off of the rest of the system while yielding positive results at low cost.
The four move engines have abilities such as: from main RAM or from ESRAM, to main RAM or to ESRAM, from linear or tiled memory format, to linear or tiled memory format, from a sub-rectangle of a texture, to a sub-rectangle of a texture, from a sub-box of a 3D texture and to a sub-box of a 3D texture.
Each of the four move engines can read and create 256 bits of date per GPU clock cycle, which equals out to be a peak throughput of 25.6 GB/s two ways.
All of the engines use a single memory path, resulting in the best throughput for all of the engines that would be the same for only one of the engines.
They share their bandwidth with different components of the GPU, like video encode and decode, the command processor and the display output. The other source typically only consume a small amount of the bandwidth.
The great thing about the move engines is they can operate at the same time as computation is taking place. When the GPU is doing computations, the engines operations are still available. While the GPU is working on bandwidth, move engine operations can still be available so long as they use different pathways.