I am having a lot of VDroop

[burhanmarvi]

i5 8600k
gigabyte z370m ds3h

Hi, I am overclocking my cpu and I am noticing that I am having A LOT of vdroop. I have my vcore set to 1.35 in bios with the LLC at trubo yet under 100% load my vcore drops down to 1.2.

I am using prime 95 to test and CPUz + HWMonitor to see system specs

 

[Supernova1138]

Your board has weak VRMs with no heatsinks, I wouldn't be surprised if the VDroop is the result of throttling because your VRMs are getting too hot. This is a problem with a lot of the entry level Z370 boards, for the most part it's not a huge issue, unless you're trying to overclock an 8700k or trying to push higher speeds out of an 8600k, then you are more likely to run into problems.

In any case, I might pare back my expectations if you're trying to break past 5.0GHz on that 8600k with that board, it really isn't suited to heavy overclocking.

 

[burhanmarvi]

How do I check If my VRMs are throttling what temperature / tool should I use?

 

[Supernova1138]

How do I check If my VRMs are throttling what temperature / tool should I use?

VRMs often do not have a temperature sensor that software can read, leaving you with the option of checking with a thermometer. What sort of cooling are you using. If it's an AIO watercooler, then you have absolutely no airflow over those VRMs and that might be contributing to the problem.

Edit: You could try Intel's Extreme Tuning Utility, this won't necessarily tell you if your VRMs are overheating, but it might tell you if you are getting throttling due to lack of power from the board, though this is usually more useful for telling if you are running into limitations under Intel's Turbo Boost than anything else.

 

[burhanmarvi]

I am using an Air Cooler, Hyper 212 EVO I downloaded the intel extreme tuning unility and ran the stress test. During load my vcore dropped to 1.260. I have provided screenshot of after result. As you can see it says "No" for vrm throttling

https://i.imgur.com/QUSFssG.png

 

[Supernova1138]

A 212 EVO is actually a bit weak for an overclocked Coffee Lake chip, what are your CPU temperatures and CPU frequencies like when the VDroop happens. If you are thermal throttling on the CPU that might explain it. If not, the board you have isn't really well suited to heavy overclocking, so if you already have your LLC maxed out and still can't hit your VCore target, then there might not be much you can do and you'll have to settle on a lower speed that is stable at a lower voltage.

 

[burhanmarvi]

A 212 EVO is actually a bit weak for an overclocked Coffee Lake chip, what are your CPU temperatures and CPU frequencies like when the VDroop happens. If you are thermal throttling on the CPU that might explain it. If not, the board you have isn't really well suited to heavy overclocking, so if you already have your LLC maxed out and still can't hit your VCore target, then there might not be much you can do and you'll have to settle on a lower speed that is stable at a lower voltage.

My temps are actually not bad at all. I get a max of 70 under full load. My Vcore is set to 1.35 and I have it at 4500 mhz. I have a feeling that although my vcore is so high it drops so much that the temps are fine for my cooler.

I have found that If I over shoot the vcore the vdroop actually makes it an acceptable voltage under load. If I were to set my vcore to say 1.45 in bios would that be OK? Considering how much the voltage drops. Given that my temperatures stay under 80 C I feel it should be ok. Or is 1.45 too high of a vcore for my VRMs?

 

[Supernova1138]

1.45V is dangerously high and I wouldn't recommend pushing that high. Even if you have VDroop going on under heavy load, you're still pumping 1.45V in under lighter load conditions and that can damage the CPU. 1.4V is the absolute maximum Vcore you should be setting and ideally you should be running lower than that. The only other things you could try is updating the BIOS and hoping a BIOS update will improve the LLC for you. Sometimes early BIOS revisions on a new platform can have some odd LLC or voltage control behaviour.

 

[burhanmarvi]

1.45V is dangerously high and I wouldn't recommend pushing that high. Even if you have VDroop going on under heavy load, you're still pumping 1.45V in under lighter load conditions and that can damage the CPU. 1.4V is the absolute maximum Vcore you should be setting and ideally you should be running lower than that. The only other things you could try is updating the BIOS and hoping a BIOS update will improve the LLC for you. Sometimes early BIOS revisions on a new platform can have some odd LLC or voltage control behaviour.

Should I reset bios to default before updating it?

 

[Supernova1138]

1.45V is dangerously high and I wouldn't recommend pushing that high. Even if you have VDroop going on under heavy load, you're still pumping 1.45V in under lighter load conditions and that can damage the CPU. 1.4V is the absolute maximum Vcore you should be setting and ideally you should be running lower than that. The only other things you could try is updating the BIOS and hoping a BIOS update will improve the LLC for you. Sometimes early BIOS revisions on a new platform can have some odd LLC or voltage control behaviour.

Should I reset bios to default before updating it?

You probably should, though it might just go to the defaults anyway after doing the update.

 

[burhanmarvi]

So I reset bios and re enabled my overclock I am getting pretty good temperatures and I used the stress test in the Intel Extreme Tuning Utility so it seems to be stable.

However due to my voltage issues I am unable to test via prime 95. I do the Small FFTs and when I start the test I get "Workers Stopped" Across all of the cores. My system does not freeze at all though.

 

[Supernova1138]

The XTU stress test isn't nearly as intensive as Prime95. Other than making sure your LLC settings are set to a higher level and doing a BIOS update to see if that improves LLC behaviour, there isn't much else to be done. Your board really isn't that well suited to overclocking due to poor power delivery, so you're kind of stuck. You can try pushing stupidly high voltages and hope the VDroop prevents you from frying your CPU in the process, but even if that doesn't happen your VRMs will probably blow after a few months of that.

 

[burhanmarvi]

The XTU stress test isn't nearly as intensive as Prime95. Other than making sure your LLC settings are set to a higher level and doing a BIOS update to see if that improves LLC behaviour, there isn't much else to be done. Your board really isn't that well suited to overclocking due to poor power delivery, so you're kind of stuck. You can try pushing stupidly high voltages and hope the VDroop prevents you from frying your CPU in the process, but even if that doesn't happen your VRMs will probably blow after a few months of that.

I understand, thanks for your guidance. Next time I upgrade my system I will make sure not to buy a cheap motherboard.