FCLK isn't read correctly sometimes


As you can see in the picture HWINFO sometimes reads out wrong frequencies. This bug persists until I restart my pc and appears to be random. It's the second time that his happens across 20 reboots I think.
Normaly I would see a static value FCLK : 1866,6 or something. Also I don't think that my PC is stable with an FLCK above 1900.


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Can you please verify with Ryzen Master what FCLK it shows in such case ?
Thanks. Was the above Ryzen Master screenshot done at the same time when HWiNFO was showing 1948 MHz FCLK ?
Let me explain it a bit better. Ryzen master shows a constant FCLK value of 1867 MHz. While HWINFO sometimes shows this crazy jumping values, so it's never constant. With sometimes I mean it will most likely disappear when I reboot. But since it the second time I see this, I think it will happen again.
I didn't reboot until now and I am still using this PC while the error is reproducable.

In short: yes. The screenshot was done while the error in HWINFO was still reproducable.
Thanks for the clarification. But just to be clear... Does it mean that normally HWiNFO shows a constant FCLK all the time, until something happens and then it start showing values that are jumping. And that continues until a reboot?
If that's true, did you perhaps perform a sleep / wake system just before the erratic values appeared ?
Normally HWINFO showed a constant value of 1866,6 MHz on idle and on load which I considered normal. And sometimes you get what I reported here. I didn't perform a sleep just the normal windows 10 shutdowns which are default on windows installations.
This is how it looks like when I did a normal shutdown and power up (after the erratic value session). I have read on reddit that the value shouldn't be fixed right?
I remember that HWINFO was able to show FCLK after sleep but with varying values between 200MHz to 1866MHz. (It wasn't capable of that before the newest stable version without going to sleep)
I added another picture that shows variance in the first decimal place (.5 to .8), which wasnt't there in the first picture on the same session.


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Thanks, I'm checking this...
Yes, earlier HWiNFO versions could report FCLK only after a sleep/resume sequence due to certain BIOS limitations. The latest version has added universal reporting, which should be more accurate. Ryzen Master on the other hand doesn't reflect certain power management states where it should be reporting a different FCLK value, not static. I'm still wondering what is causing the sudden issue, it's quite possible that a new BIOS update might fix this.
Disabling DF C-States disables power management features that include dynamic FCLK switching. So it appears to fix the "issue", but in fact it prevents the FCLK to change states.
I have the same issue. FCLK will sometimes start fluctuating in HWiNFO even though Ryzen Master shows the right frequency.

However, the same thing that is causing this is also giving me performance issues:
I know this is strange, but when HWiNFO shows those wrong readings for FCLK, my games continously stutter and I need to turn off my pc, unplug it, and turn it back on to fix both issues.
Any idea on what could be the culprit?

Here's my specs:
  • CPU: Ryzen 7 3700X
  • Motherboard: Asus TUF X570-Plus Wi-Fi
  • RAM: Viper Steel 16GB 3866MHz C18
  • SSD: Sabrent Rocket 2TB NVMe
  • HDD: None
  • GPU: MSI Nvidia GeForce RTX 2070 Super Ventus OC
  • PSU: Cooler Master MasterWatt 650
  • Chassis: Cooler Master H500
  • OS: Windows 10 Pro 1909
I also see a fluctuation in FCLK but not this kind like the users above. Bigest one I ever saw was -200MHz/+20MHz. Most of the times is a small drop below the manual set (1800Mhz) like this below or a 50~100MHz drop.
In UEFI I have manual setting of 1800MHz FCLK, MEMCLK==UCLK and the SOC/Uncore OC Mode Enabled(this disables the power savings of the IO die/chiplet)