Overclock weird after BIOS update

[BetteBalterZen]

Hey guys - I'm writing here today because I'm totally lost on what the hell happening with my PC / CPU after I updated my BIOS. 

First of all, before anyone asks, I updated my BIOS because my USB C did not work, and updating the BIOS did fix that. 

Before the BIOS update I had a 4.7GHz all core OC (Sync all cores) on my 8700K which ran just fine - ~60/70c while gaming and spikes between 80-85c in RealBench using 1.285 vcore (manual). Had a score around 1500 in Cinebench. 
Now after the BIOS update, I went to my AI tweaker, set the exact same settings as before and now my OC is going all weird. When watching my Vcore and clockspeeds while running Cinebench or Realbench, my Vcore is higher than what I set it to and my clockspeeds fluctuates between 3.8GHz and 4.7GHz and they are no longer synced, fx core 1 can be 4.7GHz and core 4 can be 4.2GHz but when I'm idle all my cores are stuck at 4.7GHz and synced up. 

I was hoping someone here could help me out, maybe tell me if I'm missing a specific feature while doing the OC now, thinking that maybe I need to configure more things than just choosing Sync all cores, setting ratio to 47 and then put in manual vcore - that is what I did before the BIOS update and it worked perfectly. 

 

Short PC specs:

8700K (Corsair H105 AIO)

ROG STRIX Z370-F Gaming

Vengeance LED 3200MHz (XMP)

Corsair HX750W (v2 GOLD)

Sorry for english grammar errors here and there, native language is Danish,

thanks

[BetteBalterZen]

I am not sure if this will bump my post up but anyways, writing this to try and bump my post up if anyone that maybe could help me haven't seen my post here. 

Again, thanks 

[unclewebb]

Sounds like your CPU is throttling.  Have you tried increasing the turbo power limits in the bios?  This is the usual cause of this type of throttling but it can also be the current limits.  HWiNFO will show you 101 throttling reasons when your CPU is loaded.  You will find a clue in there.

[BetteBalterZen]

On 3/22/2019 at 3:46 AM, unclewebb said:

Sounds like your CPU is throttling.  Have you tried increasing the turbo power limits in the bios?  This is the usual cause of this type of throttling but it can also be the current limits.  HWiNFO will show you 101 throttling reasons when your CPU is loaded.  You will find a clue in there.

Hey unclewebb, thank you for answering. 

 

So it throttles down because the CPU isn't getting enough power, is that what you mean? I did use the same amount of Vcore like before I updated my BIOS and as mentioned, it worked fine before. 

Increasing the Turbo Power limits? No, I haven't tried that. I have not done anything since this happened to me because I'm not an expert when it comes to power settings in the BIOS so I won't just try different stuff. Can you maybe tell me what that setting is called in BIOS and what it does exactly? Anything important about that settings I should know about before trying anything? 

But anyway, giving my CPU more power will result in more heat and my CPU already runs hotter now when OC'ing after updating my BIOS - makes me wonder; did my BIOS display wrong numbers before or have this BIOS update "damaged" my CPU in some way? 

I will give certainly have HWiNFO running next time I'm OC'ing again. I did not know this software could tell why a CPU throttles - that's really smart. 

Thank you again for answering. 

[BetteBalterZen]

Update: 

 

My OC is stable again; when stress testing or using Cinebench my 8700K doesn't randomly underclock under load anymore. My powerlimit was set to 130watts and I changed that to 200watts. That fixed it. I do believe though that my temps still are higher than before my first BIOS update but I am able to keep all my cores at 4.6GHz in Realbench with temp spikes hitting 81-83 c (general average temp 75/80 c) with 1.290 volts Vcore. 

 

I have a new question though and was hoping someone could help:

I have set Vcore to 1.290v in BIOS and under Realbench stresstest sometimes Vcore increases to 1.312v for a brief moment, then goes back down to 1.290v. 

Any tips? 

 

Thanks