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Sorry Freak but that is just not correct regarding the variable clock speed and how it works. Cerny made it very clear as to how it works. However a lot of people are under the assumption that PS5 can only hit its maximum clock speeds during short "boost modes" before it overheats similarly to how boost modes work on PC. However this is very wrong: there is no boost mode and also no thermal throttling. This is what Mark Cerny actually said during his talk:
- Mark Cerny himself explained that there is no such thing as thermal throttling on PS5. Instead clock speeds are dependent on the power budget of the system. PS5 is using AMDs Smart Shift technology: the available power is shifted to where it is needed most in the system. This means that graphically demanding games won't have to throttle after a short boost mode. Instead the system will recognize that the GPU needs extra power and will shift power to the GPU so that it can sustain high clock speeds. Cooling is still possible because the consoles power draw has not increased, it simply uses the available power more effectively.
[*]Mark Cerny himself stated that during testing the PS5 was able to sustain max clock speeds on both GPU and CPU for extended periods of time. How long max frequencies can be sustained depends on how power hungry the operations are that have to be performed. Not every operation requires the same amount of power. Once the maximum power budget is reached the PS5 will start prioritizing where it has to shift the available power.
[*]power consumption doesn't scale linearly with clock frequency. Mark Cerny also adressed this: lowering the power consumption by 10% doesn't mean you have to drop clock speeds down by 10%. So even if a game is so demanding that it exceeds the PS5s power budget you won't see a massive drop in clock speeds.
[*]often people claim that the actual GPU clock frequency of PS5 is only 2Ghz (resulting in 9.2teraflops). However this is solely based on the leaked chipset from early 2019 and there is no indication that this represents the clock speeds achievable on the actual PS5. Quite the opposite actually.
All of this information is readily available but people continue to get it wrong all the time, thereby confusing others as well. I also think not enough people give Sony credit for what looks to be a very smart design choice in getting the console to be as efficient as possible.
I didn't say it was throttling based on overheating (or if I did, I mistyped), it's hitting it's max power consumption. But I think thermal throttling could be an issue overall too, in addition to the max power, that pcie 4 ssd will generate a LOT heat. And Cerny is the one who called the variable clock speed, "boost mode." It's a variable clock speed no matter how it's labeled. It can't sustain those speeds or it wouldn't be variable. I watched that video several times and some of the things he said don't really add up as to why they made some of the decisions they made, except for trying to make things look better on paper than they really are.
And you're right, it's not like how boost is done on PC. The way he explained boost mode, it won't be able to boost under full load because of power constraints. It's typically the opposite on PC, where you're pushing the chip to it's maximum until it thermal throttles, which makes a lot more sense, imo.
Look, the only reason you shift power from one component to another for short periods, is because the system can't sustain them. All of this, like I said, is due to the power constraints on the ps5. There's only so much of it to go around and they clearly weren't happy with the sustained performance, so they're moving resources around based on usage. It some cases that can be helpful, but not under full load.
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