CPU Turbo Max per core

[Timur Born]

Hello.

Currently HWinfo only reports the "CPU Turbo Max" for the fastest core and then the "Turbo Ratio Limits" per concurrent cores. But unfortunately it nowhere seems to list per core Turbo Max values?



My current per core Turbo Max values would be: 59/59/56/56/56/55/58/58

Furthermore the reportec AVX2 limits are not entirely correct. While I am using an AVX offset of zero (0) my 13900K (or maybe BIOS?) seems to be hardcoded to limit AVX load to 58x. Only non AVX load is allowed to clock to 59x or 60x, AVX always stops at 58x regardless of the Turbo Max limits and AVX offset.

 

[Martin]

HWiNFO reports the per-core Turbo max values depending on number of active cores. So it's 59 when 1-4 cores are active, 57 when 6-7 cores are active.
You probably mean the per-core maximum values depending on Core Performance Order ("quality") I suppose?

 

[Timur Born]

Unfortunately I do not know what "Core Performance Order" is, something like AMD's CPPC maybe?

What I mean, though, is that CPUs do not have to use the same maximum frequency on each of their cores. By default my 13900K uses a maximum of 58x on a P cores, but via BIOS settings I changed that to different per core maxima. So instead of 58/58/58/58/58/58/58/58 my CPU uses something like 57/58/56/55/55/55/59/59. Since I am currently testing various modifications of that it would be useful to have HWinfo report those per core maxima, as often I wonder what I had set up last.

 

[Martin]

Try the new Beta build 4940. I added reporting this as "Maximum Per-core Ratio Limits (Fused):"

 

[Timur Born]

Great, thank you!

Unfortunately the values are not correct for my setup, though.

HWinfo:
55, 55, 58, 58, 55, 55, 55, 55,
43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43

BIOS:
56, 58, 57, 55, 55, 55, 59, 59
43, 43, 43, 43, 43, 43, 43, 43, 45, 45, 45, 45, 44, 44, 44, 44

 

[Martin]

HWiNFO displays the default (fused) values, not override.

 

[Timur Born]

Likely also useful, but since these never change it's only a one-time information. Overrides change a lot while working on a stable per core OC, so being able to read their current values would be useful. These override ratios also dictate Windows scheduler's priorities (it always prioritizes higher max ratio cores first).

 

[Martin]

OK, I will add this in the next build as: "Maximum Per-core Ratio Limits (Current):"

 

[Timur Born]

Wow, very nice. Thanks a lot and happy holidays!

 

[Martin]

Marry Christmas to you too!

 

[Timur Born]

Works great, thank you!

Maximum Per-core Ratio Limits (Fused): 55, 55, 58, 58, 55, 55, 55, 55, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43, 43
Maximum Per-core Ratio Limits (Current): 57, 56, 59, 59, 55, 55, 59, 59, 43, 43, 43, 43, 43, 43, 43, 43, 44, 44, 44, 44, 43, 43, 43, 43

I wonder what "OC Ratio" Limit means and whether it is connected to AVX load being hard limited to 58x on my setup (regardless of AVX offset)?

Turbo Ratio Limits (P-cores) - IA/SSE: 59x (1-4c), 57x (5c), 56x (6-7c), 55x (8c)
Turbo Ratio Limits - AVX2, Resolved: 59x (1-4c), 57x (5c), 56x (6-7c), 55x (8c)
...
Fused Ratio Limit: 85x
OC Ratio Limit: 58x

 

[Martin]

"OC Ratio Limit" is a somewhat legacy limit when the V/F curve is used on later CPUs. In such case the "Voltage/Frequency Curve:" defines respective limits.

 

[Timur Born]

Thanks for the explanation.

Turns out that "Turbo Ratio Limits - AVX2" is kind of correct. The CPU does hardlock AVX load to 58x max regardless of the AVX offset, but it still allows other cores to run non AVX load at 59x while AVX load is present on single cores.

 

[Timur Born]

Coming back to this after noticing a bug in my BIOS that reveals an apparent internal AVX list not shown by HWinfo. Currently HWinfo lists:

Maximum Per-core Ratio Limits (Fused)
Maximum Per-core Ratio Limits (Current)

I suspect that the BIOS also includes a "Maximum Per-core Ratio Limits AVX (Current)", because that is the one that seems to bug out (needs two reboots to be applied). Would HWinfo be able to read that out?

 

[Martin]

I'm not aware of an interface that would provide dedicated AVX per-core ratio limits. Maybe what you're looking for are the standard per-core limit with the negative AVX offset applied.

 

[Timur Born]

I am using an AVX offset of 0 and negative AVX offset rather seems to apply to "Turbo Ratio Limits - AVX2". And with the BIOS bug I just encountered it even even limits AVX load to lower ratios until the second reboot when per-core ratios are increased.

Example:

Core 0's ratio is increased from 55x to 58x. Booting into Windows then allows SSE load to use 58x, but AVX load still uses 55x. Only after a second reboot does AVX load also increase to 58x.

So there seems to be an internal AVX ratio table that only follows the normal table after a second reboot (and always maxed out at 58x for me).

 

[Martin]

Isn't that limit enforced due to power budget limit?

 

[Timur Born]

But for the BIOS "bug" the power budget doesn't change from reboot to reboot. After the 2nd reboot it works properly.

- Change per core max of a core from 55 to 58.
- Save and reboot: SSE = 58, AVX = 55
- (Reenter BIOS, save and) reboot with no changes made (!): SSE = 58, AVX = 58

And for the 58x hard AVX limit I don't think this is power budget related either, because I am playing with voltages a lot, sometimes to the point of instabilities and the 58x limit never changes. For perspective: my CB23 40k+ scores only needs 240 W instead of stock 290 W with some settings. So a *lot* less power than stock. It seems to be rather a limit of my Gigabyte BIOS.

 

[youse]

HWiNFO displays the default (fused) values, not override.

Thanks. You mean the Turbo Max Frequency is fused value? Could you kindly share how to read it from Intel and AMD cpu? This may be confidential, so sorry for asking.