Motherboard power limit throttling - why?

[OCD-FREAK]

I have i7 9700 + strix b360-f gaming and every time i play games i notice the CPU clock is going to 3.7GHz max and when i run XTU i get Power limit throttle notification, i went to bios > Ai tweaker > power saving and performance > chose performance mode and now the CPU is going to 4.5GHz, i dont think this is normal that you have to set power to performance mode for the CPU to turbo boost without power throttling, what do you guys think? 

[Tetras]

9 minutes ago, OCD-FREAK said:

i dont think this is normal that you have to set power to performance mode for the CPU to turbo boost without power throttling, what do you guys think? 

Can you please list the exact setting that you changed and under which category it was found. It is not clear from the manual, which setting you have changed.

[OCD-FREAK]

5 minutes ago, Tetras said:

Can you please list the exact setting that you changed and under which category it was found. It is not clear from the manual, which setting you have changed.

Under Ai tweaker there is "power saving and performance" i chose "performance" for the CPU to turbo boost to 4.5GHz

[OCD-FREAK]

17 minutes ago, OCD-FREAK said:

I have i7 9700 + strix b360-f gaming and every time i play games i notice the CPU clock is going to 3.5GHz max and when i run XTU i get Power limit throttle notification, i went to bios > Ai tweaker > power saving and performance > chose performance mode and now the CPU is going to 4.5GHz, i dont think this is normal that you have to set power to performance mode for the CPU to turbo boost without power throttling, what do you guys think? 

 

[Tetras]

2 minutes ago, OCD-FREAK said:

Under Ai tweaker there is "power saving and performance" i chose "performance" for the CPU to turbo boost to 4.5GHz

I think the manual is wrong (typo?), it doesn't describe what this does properly and mentions memory frequency 

[OCD-FREAK]

Just now, Tetras said:

I think the manual is wrong (typo?), it doesn't describe what this does properly and mentions memory frequency 

the full motherboard model is strix b360-f gaming but im asking like in general is this normal?  

[Tetras]

Just now, OCD-FREAK said:

the full motherboard model is strix b360-f gaming but im asking like in general is this normal?  

The manual doesn't adequately describe what that setting does, so I'm afraid I can't say if this is, or is not normal.

 

The only way of getting more information that I can think of, is turning the option back to Auto and then checking stuff in hwinfo (like PL1/PL2 and TAU) and writing them down, then switching it back to Performance and checking the new values.

 

I suspect that this setting on Auto is actually enabling the power saving mode.

[porina]

Probably working as intended. Intel CPUs have two main power limits, called short term and long term. For non-overclocking platforms/CPUs, default tends to respect those values. You get a higher power limit for a short time, then it will settle down to the long term power limit. Some boards allow you to run at the higher power limit all the time.

 

Why the lower power limit? That's the TDP and is the minimum cooler specification to run the CPU at spec, like if you're using the stock cooler or something similar. Intel of the past allowed system builders to choose the final power limit without affecting warranty as it didn't count as overclocking, until it blew up with Raptor Lake. AMD did enforce their stock power limits on Ryzen, although I don't know what their current policy is.

[OCD-FREAK]

10 minutes ago, porina said:

Probably working as intended. Intel CPUs have two main power limits, called short term and long term. For non-overclocking platforms/CPUs, default tends to respect those values. You get a higher power limit for a short time, then it will settle down to the long term power limit. Some boards allow you to run at the higher power limit all the time.

 

Why the lower power limit? That's the TDP and is the minimum cooler specification to run the CPU at spec, like if you're using the stock cooler or something similar. Intel of the past allowed system builders to choose the final power limit without affecting warranty as it didn't count as overclocking, until it blew up with Raptor Lake. AMD did enforce their stock power limits on Ryzen, although I don't know what their current policy is.

the cpu is going to 4.5ghz or a second then awfully downclocking to 3.7ghz, its i7 9700 that has base clock of 3ghz and max 4.7ghz, why is that when i set power management in bios to performance mode it clocks to 4.5ghz? is that normal to play around with bios for a cpu to boost clock as it should under load?

[porina]

21 minutes ago, OCD-FREAK said:

the cpu is going to 4.5ghz or a second then awfully downclocking to 3.7ghz, its i7 9700 that has base clock of 3ghz and max 4.7ghz, why is that when i set power management in bios to performance mode it clocks to 4.5ghz? is that normal to play around with bios for a cpu to boost clock as it should under load?

Boosting is opportunistic, it is NOT guaranteed to be hit or sustained in all conditions. The max turbo clock listed is typically achieved only if a single core is loaded and nothing else is limiting. The all core turbo clock is lower again. Looking up the 9700 here, it actually does a little better than most. Apparently the max turbo clock is 4.7 GHz for up to two cores used. The 4.5 GHz is for when 5-8 cores are used.

 

It dropping down quickly to 3.5 GHz is due to the long term power limit. This is intended because most system builders will use the minimum cooler they can get away with. If you set it to performance mode, it likely sets the long term limit to equal the short term limit. If the cooling is good enough, you can enjoy that higher performance.

 

If you really want to understand how it works, I suggest reading the interview below which is the best I've seen it covered.

https://www.anandtech.com/show/14582/talking-tdp-turbo-and-overclocking-an-interview-with-intel-fellow-guy-therien