Don't understand Vcore

[Hallowenman]

I have some questions about overclocking as I am not very experienced with it. For some time now I have been running my i5 6600k at 4.4 GHz without any problems, not a single blue screen or other issues. Temps are fine, and I have been running it daily like this for over 6 months. To get to 4.4 GHz I simply used the auto overclock feature in the bios, and didn't change a thing. The auto overclock has a setting for 4.4, 4.6, 4.8 and 5.0 I think. Trying any auto setting over 4.4 results in immediate blue screen once I get past the bios during startup. 

 

But now I am trying to do better with manual overclocking. I can get it to boot into Windows without any issues, but give it some time and I get a blue screen. At 4.6 I have tried adjusting vcore a lot to see if I can find a stable setting, but it doesn't seem to work. I have set vcore to "fixed" in the bios, and I still got blue screen when going for 1.4 vcore. When comparing to other users on different forums it seems like a lot of people manage 4.6 at 1.4 or less, but I do understand that not all chips will be able to do this. However I noticed in HWMonitor, CPU-Z and ASRock A-Tuning that it reads a lover vcore value compared to what I set it to. Right now I am testing 4.5 at 1.38 to see if it will run stable, but all programs read lower values, anywhere from 1.312 to 1.360, but never higher. During AIDA64 stability test it was at about 1.328 for most of the time even though it is set to fixed 1.380. What am I missing here? In the bios I have all cores on 4.5 at the moment, 4.3 cache ratio, fixed vcore at 1.380 and Speedstep off. Everything else is on Auto I think. Minimum cache ratio might also have been set to 43 or Auto, and BLCK Frequency might be on Auto or 100.0

[VaynardX]

What you are experiencing is what is known as VDroop. That means that when you stress test or put load on your computer, it will actually not feed what you set on the motherboard unless if you tinker with your mobo's LLC settings. Not all motherboards have this option, but your mobo probably has it. LLC stands for load line calibration and you may want to experiment with that to get the voltage that your system needs to get stable.

 

That being said, I really do not trust the automatic overclocking feature of some motherboards because, if anything, it just feeds your procie may way too much voltage than it ever needs. Overclocking is something that requires a lot of time and testing, but if you can manage, you will have unlocked the full feature of your processor and get to enjoy it for a long time.

[Hallowenman]

20 minutes ago, VaynardX said:

What you are experiencing is what is known as VDroop. That means that when you stress test or put load on your computer, it will actually not feed what you set on the motherboard unless if you tinker with your mobo's LLC settings. Not all motherboards have this option, but your mobo probably has it. LLC stands for load line calibration and you may want to experiment with that to get the voltage that your system needs to get stable.

 

That being said, I really do not trust the automatic overclocking feature of some motherboards because, if anything, it just feeds your procie may way too much voltage than it ever needs. Overclocking is something that requires a lot of time and testing, but if you can manage, you will have unlocked the full feature of your processor and get to enjoy it for a long time.

The only setting related to LLC I seemed to find was to set it to Auto, Level 1, 2 or 3, where Level 1 should be the best for voltage and overclocking according to the help text. I might have missed something, I could check the mobo's documentation.

 

But shouldn't it at least get close to the fixed vcore value when the system is idling? Right now when I am not stressing the system I get 1.355 to 1.360 max, which is still not close to 1.380?

[Hallowenman]

Finally found this on another forum; https://www.overclock.net/forum/6-intel-motherboards/1637288-asrock-z170-pro4s-fixed-voltage-setting-not-working.html

Seems like it might be a VRM quality issue with the ASRock Z170 Pro4s board?