No, it's not running on magic. We need to stop this now. There are a few very clear possibilities here and all of them are with info we've known for several months now:
[For PlayStation 5]
1: The PS5 GPU cache scrubbers are being leveraged
2: The PS5 GPU's faster clock speed benefits more current-gen engines or engines affected by clock speeds more than wider GPU designs
3: The PS5's I/O memory subsystem is more robust both on paper and in practice with keeping and feeding data to memory as needed
[Against Series X]
1: There is a larger bandwidth penalty on the segmented fast/slow memory pools than anticipated (either due to design or due to software OS/kernel and/or GDK API settings that have to be optimized)
2: The I/O memory subsystem is suboptimal either out of design or due to lack of feature availability (DirectStorage is not readily available for PC developers until quite later in 2021, so many 3P devs might not be leveraging that part of XvA. And if they aren't leveraging that, they also aren't leveraging SFS)
3: The CPU is not fast enough to keep up with drawcalls for GPU while also needing to handle data transfer between the fast/slow memory pools and some overhead (1/10th of a core according to MS) for the XvA I/O memory subsystem when SMT is enabled (this can be "solved" by simply clocking the CPU higher, if the thermals allow for it, through a firmware patch)
4: The GPU clock is 405 MHz slower than PS5's plus lacks hardware cache scrubbers, which can have a negative impact on game engine that are built with narrower GPU designs in mind and more reliant on faster GPU clocks (majority of current-gen game engines are this way)
...if we start to see consistent performance in favor of Series X later in the year, then those advantages can simply be explained as:
[For Series X]
1: The system is able to maintain data transference between fast/slow memory pools optimally
2: GPU-bound memory has a 112 GB/s bandwidth advantage over PS5's GDDR6 memory bandwidth
3: The GPU is wider, so more work can be issued and processed simultaneously per issue compared to PS5
4: The I/O memory subsystem has all components readily available and in use; even if I/O memory subsystem performance in
isolation still favors PS5, the gulf could be at a point where the difference is not large enough to negatively impact the other
aforementioned advantages (higher bandwidth in GPU-optimized pool, 100 MHz faster CPU clock, lowered overhead of hardware
resources by system in general, etc.)
Also worth adding that while Series X's audio might be somewhat less sophisticated than Tempest Engine, it also requires less memory
bandwidth most likely. Meaning less of a squeeze by the audio and that leaves even more for the GPU, under intense audio workloads. Of
course, all of
these points are
IF the performance metrics swing in favor for Microsoft longer-term; currently that is not the case.
