Silent_Buddha
Legend
Strange, since AVX is highly intensive on calculations.
Where can I read that?
On "the road to PS5" Cerny mentioned that AVX 2.0 required to drop clocks. And it´s also a Zen 2.
On a normal CPU there's a base clock and a boost clock. The CPU will do what it can to reach the boost clock, but if it can't do that due to heat or power limits, it'll start dropping until it reaches the base clock.
For example, the Ryzen 3700x has a base clock of 3.6 GHz and a boost clock of up to 4.4 GHz.
In normal use, including games it'll likely be in the 4.2-4.4 GHz range across all cores. Closer to 4.2 GHz if all cores are being highly stressed, closer to 4.4 GHz if only a few cores are being highly stressed.
It'll rarely drop to the base clock while in use. However, if AVX 2.0 is heavily leveraged it's possible it might drop down to the 3.6 GHz base clock.
The XBSX's locked frequency is likely to be analogous to the base clock of a Zen 2 CPU (like the 3700x). If the XBSX had a boost clock, then AVX 2.0 would certainly drop it down.
Since MS want consistency in performance when all aspects of the SOC are being used, the CPU and GPU are clocked conservatively so that developers can still rely on the performance even if they are approaching full occupancy of the CPU and GPU.
Basically assume that the XBSX is using the base clocks of a Zen 2 CPU rather than the boosted clocks.
The same goes for the GPU. MS is taking the approach of a locked deterministic clock on the GPU similar to desktop GPUs prior to NV and then later AMD introducing boost clocks.
There are benefits beyond consistent performance, however. Going conservative with clocks means that MS are likely to have better yields on the SOC and potentially a lower power consumption due to being below the "knee of the curve" WRT power and frequency scaling. Both of those will help reduce the overall cost of the console to MS.
The downside is that depending on how the CPU is used there is untapped power not being used versus clocking the SOC closer to the limits of the silicon like Sony are doing with the PS5.
Regards,
SB
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