I just found this video about some guy “fixing” Ryzen 7000 high-temp mode by lowering the power limit in order to get stock performance at lower temps. Does this make any sense? IMO one of the interesting things about Ryzen 7000 is precisely the high-temp mode and it makes more sense to me to let it run as specified and try to squeeze out maximum performance through better cooling, airflow and undervolting. Limiting the power input feels like disabling one of its features for no reason. This is the video: Fixing Ryzen 7000 - PBO2 Tune (insanity) - YouTube
Isn’t this called ECO mode ?
I think Ian Cutress is going to be doing a full video on how limiting the socket power will do wonders on this very thing too.
This is probably the same deal then 
There’s a discussion happening over here.
I think what we’ll see with Zen 4 is that there is such a thing as a cooler that’s too good and allows power consumption to keep ramping up well beyond the power efficiency sweet spot. This is why some reviewers are seeing e.g. the 7950X run 40% faster than the 5950X but consume twice as much power in a given benchmark. Pay particularly close attention to the cooler each reviewer is using. GN is using a Liquid Freezer II at full fans and clocking some of the worst efficiency numbers.
I think limiting PPT (and potentially TDC/EDC as well) is going to be one approach that works in some cases, like if there’s a known heat dissipation capacity in a case or room, or a specific section of the efficiency curve that you want to stay within. Heck, I do this today with some systems that I know to be thermally-constrained due to poor airflow or other factors: ECO mode!
The other option will be to right-size your cooler. I’m eager to see reviews of e.g. the 7900X with a decent tower cooler like the Noctua NH-U12A or Scythe Fuma 3. I bet the efficiency numbers will be through the roof (in a good way) without lowering thermal throttle or power limits. And performance will be close to what we’re seeing in these initial reviews.
Here’s the issue, though: if any meaningful load pushes Tctl/Tdie to ~95ºC, the CPU fan (and any other fans tied to the CPU temperature) will constantly ramp up to full speed. Sure, you can lower the maximum duty cycle to X%, but that just means the fans will constantly ramp up to X%. What are our options for sensible fan curves with this new paradigm? Can we key fan curves to power consumption metrics or something else?
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It makes lots of sense. In fact, you should always do that for Zen4. A decent German publisher found that 60% of stock power limit retains 95% of top performance across a bunch of different workloads.
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Wendel was saying this in his AM4 Linux video on the 26th Sep. You can knock off a lot of power and still be at 95% performance. It seems to me you could save loads of money on a cooler if you just did that instead.
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What if instead your goal is to get maximum performance (on a regular high-end cooler or water cooling) instead of lowering temperatures? Is undervolting and improving cooling the way to go?
Derbauer found delidding allowed 20C cooler.
I think the built in options are probably the way to go until someone figures out details. The built in option for running the CPU at low power is like buying a 1000w PSU for a 400w system. The fan never comes on so it’s quiet.
You really don’t have to screw the last gram of performance from your computer if it’s already faster than 90% of the computers. Having it stable and quiet counts for more. It depends what you’re going for.
My machine is not at all tuned but it’s high spec. Very stable, I don’t waste time trouble shooting why it crashed when I asked it to do something hard It always just does it. I have other hardware to tinker with.
From around 30 minutes in Steve tests the stock boost vs temp using LN2.
But in short it’s like Zen 3, but even more so: More cool → More Better.
Delidding + undervolting + water cooling makes the most sense to me so far. That’s what I am planning to do to my future 7950x. Now I just have to figure out what RAM will not bottleneck it.
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