Why doesn't PBO2 hit the same allcore clocks as setting manually?

Man of Honour
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I have a 5900X. If I manually set a 46.75x ratio then it runs at a fixed 4675mhz across all cores.
If I put ratio on Auto and enable PBO2 it tops out around 4.4-4.5ghz allcore under load, however single cores boost to about 4875mhz.

This is a bit annoying, clearly a manual overclock is best for multithreading (over 10k in cpu-z bench) but single thread suffers. What I really want is it to run all cores at 4675 but also boost cores higher when needed for single threaded apps. At the moment it feels like I have to choose; if I want good multithreaded performance I have to manually set it and suffer low single thread clocks; if I want good single thread clocks I have to use PBO2 and suffer low allcore clocks.
 
Soldato
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PBO is conservative to maintain system stability that's why you will get 200-400mhz higher with a manual OC
 
Soldato
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I have a 5900X. If I manually set a 46.75x ratio then it runs at a fixed 4675mhz across all cores.
If I put ratio on Auto and enable PBO2 it tops out around 4.4-4.5ghz allcore under load, however single cores boost to about 4875mhz.

This is a bit annoying, clearly a manual overclock is best for multithreading (over 10k in cpu-z bench) but single thread suffers. What I really want is it to run all cores at 4675 but also boost cores higher when needed for single threaded apps. At the moment it feels like I have to choose; if I want good multithreaded performance I have to manually set it and suffer low single thread clocks; if I want good single thread clocks I have to use PBO2 and suffer low allcore clocks.

Have you tried using the curve optimiser?
 
Man of Honour
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Yes, this is with curve optimiser. Haven't necessarily got the optimal settings, but it's kind of working correctly for single core, it boosts to 4.9ghz. The issue is the clockspeed is too low when all cores are loaded, I'm not sure how to improve that with curve optimiser
 
Caporegime
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This is exactly why Asus introduce their dual OC feature on the Dark Hero. PBO won't push all core clocks high enough for whatever reason.
 
Associate
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PBO won’t fine tune. It’s a good tool, but as expected, someone with more knowledge and willing to invest some time will achieve better results.
Usually any auto overclock/tuning tool will be too generous with voltage, causing the chip to run hotter than it should, affecting the final numbers.
Previous version Ryzen (3900x), also previous version of PBO using a negative offset voltage would kind of balance things out, as long the user wasn’t too greed and starved the chip.
 
Soldato
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iv done some testing in a thread on here somewhere. for me ppt was the key figure that governed all core clocks on high load in prime avx. 65w and all cores would run 3.8 ghz ish . 115w and all cores would do 4.3ghz ish.
 
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