No turbo boost on i5-7600?

pfpv

I hope it's the right subforum to post in. I run 2.7.2 on an i5-7600. Its base frequency is 3.5 GHz and Max Turbo Frequency & Intel Turbo Boost Technology 2.0 Frequency is 4.1 GHz. I read somewhere that if turbo boost is enabled I should see Max: 3501 MHz or Max: 4101 MHz in Dashboard, i.e., with "1" at the end. But see only Max: 3500 MHz. Sometimes I see strange current frequencies, though, like Current: 1601 MHz or Current: 1398 MHz but never see anything above 3500.

I have Intel Speed Shift enabled with core level control and power preference set at 95% (previously 80%). PowerD is disabled.

Can anyone explain why I don't see turbo boost frequencies?

stephenw10

Frequencies with 1 at the end do indicate turbo active in Speed Step. I'm not so sure about in Speed Shift.

Can you enable speed step instead?

pfpv

@stephenw10, did you mean PowerD by Speed Step? But supposedly Speed Shift is so much better. Should I bother with PowerD? Does it also mean that speed boost is not available with Speed Shift?

stephenw10

Powerd is what controls Speed Step in pfSense/FreeBSD when it's enabled. If Speed Shift is enabled it overrides powerd by controlling the CPU frequency directly.

Yes Speed Shift is, in general, far better than Speed Step because it can shift frequencies far faster and do it per core.

However if you disable speed shift and enable speed step instead you can see what frequencies it runs at, if they are what you expect.

pfpv

@stephenw10 said in No turbo boost on i5-7600?:

However if you disable speed shift and enable speed step instead you can see what frequencies it runs at, if they are what you expect.

Yes, I realize that it's either Speed Step or Speed Shift. But if admittedly Speed Shift is better why would I want to use Speed Step? I assume that Speed Shift would use turbo frequencies. Do you know why it's not using them? Or my assumption is incorrect?

stephenw10

I have no idea why it's not using them. Or even if it's actually not using them. It might be just indicating incorrectly.

I suggested using SpeedStep as a test because we know how that should respond. If that also shows some far lower frequencies it could be a bad table in the BIOS.

pfpv

@stephenw10, I see, thank you for the explanation. I did change to Speed Step, rebooted and that line showing current and max frequencies disappeared from the dashboard. Now I have only this:

Intel(R) Core(TM) i5-7600 CPU @ 3.50GHz
4 CPUs: 1 package(s) x 4 core(s)
AES-NI CPU Crypto: Yes (active)
QAT Crypto: No

With Speed Shift I had current and max frequencies listed in the second line. Do you have an idea what happened? I think those frequencies should be listed there.

P.S. Doing

sysctl -a dev.cpu | grep 'freq_levels\|freq'

does show

dev.cpu.0.freq_levels: 3501/65000

And sometimes

dev.cpu.0.freq: 3501

for all 4 cores. So, it's probably a displaying issue.

pfpv

I changed back to Speed Shift. The line

Current: 1601 MHz, Max: 3500 MHz

is back. Max has no "1" as last digit.

sysctl -a dev.cpu | grep 'freq_levels\|freq'

now shows just

dev.cpu.0.freq_levels: 3500/-1

Before, it had a long line listing all possible frequencies, I think. Maybe "-1" indicates a possibility of turbo now?
Also, current frequencies sometimes have "1" at the end:

dev.cpu.0.freq: 1601

stephenw10

The second value there indicates the expected power consumption. It's passed by the BIOS ACPI tables. I imagine it just doesn't pass anything when speedshift is enabled.

Yes I would expect a long list of levels when speedstep is enabled. You did see that?
It was showing the expected value (3501) there though.

If speed shift is enabled per core do you see up to 3500 on any one core?

pfpv

@stephenw10 said in No turbo boost on i5-7600?:

Yes I would expect a long list of levels when speedstep is enabled. You did see that?

Yes, I saw a long list of values, frequency/some number which was probably the expected power consumption as you say. I didn't paste all of them here.

It was showing the expected value (3501) there though.

Yes. Speed Shift doesn't show it, though.

If speed shift is enabled per core do you see up to 3500 on any one core?

Whatever I did I couldn't push it all the way to 3500. I did speed tests passing 3/3 Gbps down and up. I am on fiber with PPPoE and limiters, and even PPPoE with limiters didn't do it. I watched with "top" and the system CPU utilization came close to 50% and then went down. I don't really need turbo frequencies. I was just checking if everything is as expected as I changed the hardware recently (from a similar PC with an i5-3xxx CPU) and transferred the config. There was no Speed Shift on the i5-3xxx (forgot the digits), so it's new to me. There was only Speed Step.

When I briefly tried Speed Step on this new (for me) i5-7600 the frequency did go close or to exactly 3500 MHz when pushing. As expected all cores had the same frequencies. With Speed Shift cores sometimes had different frequencies. Speed Shift is so much more efficient given my observations.

Also, this made me think that with Speed Step where all cores have the same frequency, Turbo frequencies are not possible because by Intel specs only one core can have the max frequency and 2-3 cores - lower turbo frequencies. And all 4 cores can only nave the nominal frequency at the same time. If Speed Step can only vary frequencies of all cores at the same time they will never be turbo.

stephenw10

Hmm, it's possible it just never get's pushed hard enough. What happens if you set the power preference to something much nearer the performance end, say 20?

pfpv

@stephenw10, yes, that did it. Sample output:

dev.cpu.3.freq_levels: 3500/-1
dev.cpu.3.freq: 1450
dev.cpu.2.freq_levels: 3500/-1
dev.cpu.2.freq: 3903
dev.cpu.1.freq_levels: 3500/-1
dev.cpu.1.freq: 3903
dev.cpu.0.freq_levels: 3500/-1
dev.cpu.0.freq: 3903

It went above 3500 on 3 cores. with a "3" at the end for some reason. The reported frequencies are kind of strange. Another sample output:

dev.cpu.3.freq_levels: 3500/-1
dev.cpu.3.freq: 1142
dev.cpu.2.freq_levels: 3500/-1
dev.cpu.2.freq: 1184
dev.cpu.1.freq_levels: 3500/-1
dev.cpu.1.freq: 1601
dev.cpu.0.freq_levels: 3500/-1
dev.cpu.0.freq: 2001

But think it's cleared now. Turbo frequencies work. My system just doesn't need them. Speed Shift works very well. Thanks for your help!

P.S. Speed Shift was at 95 before. I am setting it back to 95.

stephenw10

Ah, nice! I run that at 80 on an i5-6400T for reference. Seems about optimal for my use but that's just a test box, it's not always on.