PaintTinJr
Gold Member
But is the option of the Tempest Engine - which should be far better than either CPU/GPU physics acceleration - maybe part of the answerFrom the discussions I'm seeing on more technical forums I think that I get what happened.
Both Microsoft and Sony have strong concerns about heat and prevent throttle, each one addressed this issue in different ways. Microsoft's way is more simpler, just put a bigger cooler. Both solutions work but are fundamentally different, Microsoft way deals with the heat after it's generated, Sony tries to prevent the heat from being generated.
This is the FPU is the single greatest source of heat, so Sony went with a smaller FPU to have a CPU that generates less heat, used less power, don't throttle and is easier to cool.
Form analysing the die shots people are concluding that Sony made AMD remove the FADD from the FPU leaving only the FMAC. The FPU can still do FADD math at native 256bits, only on more cycles than the dedicated FDAA unit. So the FPU works the same, with a bit less throughput, and do this generating much less heat and using much less power to prevent the CPU from downclocking when stressed. This is really interesting!
Edit: contrary to what some say, the CPU may be better than GPU in doing physics if the right engines are used, because today's CPU have strong vector capabilities. With a 256bits FPU the CPU can calculate the physics of 8 objects with 32bits precision every 5 cycles (the number of cycles the Zen 2's FPU takes to do FADD math at the FMAC, some say).
Edit2: and the SeX would be able to do 8 additional calculations simultaneously every 3 cycles while turning into a blast furnace.
I'd be thinking that if you can offload to a far more effective device for physics then you might make the argument to cut functionality to the minimum on the CPU, both encouraging use of the Tempest engine, and get more performance for proportionally less power draw, and less heat.