Why is my Core i5 9600K running so fast?

[JKist1]

I understand my 9600K has a base frequency of 3700 MHz and a turbo speed of 4600 MHz. As observed by both ASUS Suite 3 and CPU-Z, my CPU's operating frequency fluctuates between 4300 MHz and 4600 MHz. I have not seen it higher or lower yet.

CPU temperature starts at 30-32 C, goes into the mid-50's C after gaming, then settles back down to the mid-30's C. As far as I know, I have not switched on any overclocking options. The only BIOS modification I recall making was to select "XMP-I" because my RAM started out at a standard 2133 MHz speed. After selecting the "XMP-I" option the RAM kicked up to its advertised speed of 2666 MHz.

ASUS Prime Z390-A motherboard

Core i5 9600K CPU

Seasonic Focus Plus Platinum PSU @ 850 W

Ballistix Elite RAM, DDR4 2666

Noctua NH-U9S cooler

MSI 1070 Ti graphics

My old Win 7 machine has an i7 3770K and its frequency fluctuates between 1600 MHz and 3900 MHz while the new i5 9600K never appears to drop down to even its base frequency never mind parked-at-the-curb speeds.

Is it the selection of the XMP-I option that gooses the CPU also or is it something else, perhaps some option I clicked accidentally before saving out of the BIOS setup?

[n_scott_pearson]

Check your BIOS configuration. There may be parameters that lock the processor in high-performance mode.

...S

[JKist1]

ASUS has also suggested I try entering BIOS and going back to the Default settings. I suppose it can't hurt. The only changes I remember making was to enable the XMP-I profile and maybe fiddling with the fan speed control profiles. I'll try and see.

[n_scott_pearson]

You fiddled with the fan speed control profiles and you have an overheating issue. Coincidence? Hhmmm...

...S

[JKist1]

"CPU temperature starts at 30-32 C, goes into the mid-50's C after gaming, then settles back down to the mid-30's C. As far as I know, I have not switched on any overclocking options. The only BIOS modification I recall making was to select "XMP-I" because my RAM started out at a standard 2133 MHz speed. After selecting the "XMP-I" option the RAM kicked up to its advertised speed of 2666 MHz."

Not an overheating issue, it's a CPU-stuck-on-Turbo Boost-speed issue. Actually, if the CPU is running at 4400 MHz-4600 MHz all the time, as I suspect, I'm a little surprised it isn't running warmer. The Noctua NH-U9S seems to be doing a good job. All I did was switch from the "Silent" fan profile to the "Standard" fan profile.

[n_scott_pearson]

As I said before, check your BIOS configuration carefully. There may be parameters that lock the processor in high-performance mode - and this may be the default (makes their board look better on paper).

...S

[JKist1]

I am looking but so far I don't see what it might be unless its disguised behind euphemisms.

I have an ongoing dialog with ASUS and I'm waiting to see if they come up with an answer. I'm not expecting much.

It may be that what I am seeing is normal behavior. The Z390 chipset and 9th Gen CPU are very new.

[JKist1]

I tried reverting to the BIOS defaults as ASUS suggested. That caused my RAM to drop down to a stock 2400 MHz. After rebooting I noticed that the CPU speed would occasionally drop down to a slow speed but only very briefly (1-2 seconds) and not often. It was still spending virtually all of its time running near its Turbo Boost speed (4300 MHz-4600MHz.

I went back and re-enabled "XMP" in the "Basic" BIOS screen and that triggers the selection of "XMP-I" in the "Advanced" BIOS screen. I made no other changes.

The computer is running great, I'm just concerned that running the CPU so fast all the time may be harmful to it. If the CPU is not being harmed then I am delighted to have my CPU averaging 4400MHz.

ASUS asked me for some additional information and I'm waiting to hear back from them.

[JKist1]

An update to my issue:

Keeping an eye on the Driver downloads page for my mother board because it is such a new model/new chipset/new CPU, I noticed ASUS had posted a new download relevant to my mobo. It is an update to the latest version of the Intel RST. The update was posted 1-2-2019. I grabbed it 2 days later and installed it.

A couple of days after I updated the IRST I happened to open ASUS Suite 3 to check the mobo's vital signs and I saw that the CPU behavior seems to have changed. Instead of staying up around 4300-4600 MHz, it now idles down to its minimum speed of 800 MHz quite often then goes up to at or near Turbo speeds when working and makes brief stops at a variety of frequencies in between. This changed behavior is much closer to what I expected when I brought the new machine online. It also results in slightly cooler CPU temps and lower fan speeds when the CPU is idled down.

During this period, I also visited the Windows Power Management page. It was set to the default "Balanced". I opened the details to see what those "Balanced" settings were, checked them out, then saved out of the screen leaving the setting on "Balanced". Can those Balanced settings be tweaked without changing the designation of "Balanced" or does it switch to "Custom" as soon as you make any change?

So, what changed the CPU behavior?

1) Machine became more fully "burned in" since coming online and settled down? meh.

2) New version of Intel RST had some effect? meh.

3) Did I inadvertently overwrite a "tweaked" Balanced Power Setting with the default "Balanced Power Setting? meh.

Machine is still running great but these little mysteries nag at me. I'll probably never know for sure what changed the CPU behavior.

[ssote]

It is the turbo frequency that makes it run fast.