Today is the big Xbox Series X day, as Microsoft decided to lift the curtain on the next-generation console's full system specifications.
On paper, it already looks like an incredibly powerful game machine. However, real-world performance is even higher than that thanks to the tight hardware-software integration and optimization done by Microsoft.
For instance, Xbox system architect Andrew Goossen revealed to Eurogamer's Digital Foundry that the regular 12 TFLOPs figure for Xbox Series X effectively bumps to over 25+ TFLOPs when doing raytracing operations.
Without hardware acceleration, this work could have been done in the shaders but would have consumed over 13 TFLOPs alone. For the Xbox Series X, this work is offloaded onto dedicated hardware and the shader can continue to run in parallel with full performance. In other words, Series X can effectively tap the equivalent of well over 25 TFLOPs of performance while ray tracing.
Xbox Series X goes even further than the PC standard in offering more power and flexibility to developers. In grand console tradition, we also support direct to the metal programming including support for offline BVH construction and optimisation. With these building blocks, we expect ray tracing to be an area of incredible visuals and great innovation by developers over the course of the console's lifetime.
The Xbox Series X is also 'overperforming' in terms of IO rate thanks to the brand new DirectX extension, DirectStorage. According to Goossen, it would take a PC with 13 Zen 2 cores to match the full IO rate of the new console.
DirectStorage is less latent and it saves a ton of CPU. With the best competitive solution, we found doing decompression software to match the SSD rate would have consumed three Zen 2 CPU cores. When you add in the IO CPU overhead, that's another two cores. So the resulting workload would have completely consumed five Zen 2 CPU cores when now it only takes a tenth of a CPU core. So in other words, to equal the performance of Xbox Series X at its full IO rate, you would need to build a PC with 13 Zen 2 cores. That's seven cores dedicated for the game: one for Windows and shell and five for the IO and decompression overhead.
DirectStorage is coming to Windows PC, too, which is great news for PC gamers as well. We look forward to learning a lot more about these new features in the coming months.