I5 8600k Voltage Drops

[samuelbowater]

Hi all.

I've recently just upgraded to a I5-8600k from a I7-4790k(Which I had overclocked to 4.8ghz). I planned to overclock the cpu to 4.8ghz to start with but i've been having problems with performance/stability as the voltage does not stay constant(1.3 in bios but 1.21 under load). I have all the c states turned off in bios and other power saving options (I even have high-performance set on windows.)

Also running the cpu in Cinebench R15 gets a score of 920-940, which is quite low compared to other people?

Any advice on what to do will be appreciated or even just to say that i've got a bad component, etc...

My current specs are:

CPU: I5-8600k
CPU-Cooler: Corsair h100i GTX
GPU: Nvidia 1060 6gb
RAM: Corsair Vengeance 16gb 3000mhz
MB: Gigabyte z370p d3
PSU: Corsair 650i

 

[norcalsc]

did you perform fresh win 10 install? if not you need to as it usually leads to issues

 

[atomicWAR]

Vdroop/ load line calibration settings? if they aren't enabled I would try that now.

 

[MCMunroe]

Why are you fighting for more voltage all the time. A constant high voltage is a waste of heat and power when not under load.
Have you looked at the settings in Intel Extreme Tuning Utility?
Also with v-droop settings one does not get the set fixed voltage during use.

 

[samuelbowater]

I reinstalled windows 10, but its not activated (which I cant see that being the problem)

I had load line calibration on Turbo.

I havent looked in Intel Extreme Tuning Utility yet, what would I be looking at in the program?

 

[crestfall4]

hi, trying to help here cause im using the i5 8600k 4.8ghz with 1.26 core volt.

your cinebench results is weird because 4.8ghz i got somewhere like 1160-1180 score.

i think you should set the voltage to 1.26-1.28 and set the Loadline calibration to mode 4 or mode 3. im not sure what turbo does on LLC.

try it and do stability test using prime v26.6 and aida64 or intelburner test(optional cause it uses avx)

 

[atomicWAR]

hi, trying to help here cause im using the i5 8600k 4.8ghz with 1.26 core volt.

your cinebench results is weird because 4.8ghz i got somewhere like 1160-1180 score.

i think you should set the voltage to 1.26-1.28 and set the Loadline calibration to mode 4 or mode 3. im not sure what turbo does on LLC.

try it and do stability test using prime v26.6 and aida64 or intelburner test(optional cause it uses avx)

Yeah he is pointing you right and why I asked your LLC settings...I helped someone earlier today who was trying to bring voltages down from 1.334 to under 1.3 for a i9 9900K with LLC set to 6 for a 5ghz OC with 77C max temps. But with an increase of the LLC to 7 he could actually drop his Vcore all the way down to 1.275V and remain stable because increasing LLC decreases fluctuations in voltage to increase stablity at the cost of increased heat. So yeah try turning up the LLC settings and see if that helps.

 

[samuelbowater]

My motherboard only has two LLC settings: Turbo and High.

I think my motherboard is the problem as I did opt for the cheapest one I could find.

 

[atomicWAR]

My motherboard only has two LLC settings: Turbo and High.

I think my motherboard is the problem as I did opt for the cheapest one I could find.

You likely right. Two components i tell folks to never go cheap on is the PSU and the motherboard. They are the drivers of everything in your system. For a PSU I suggest the best quality always IMHO (tier 1 or 2) but a motherboard you want at least a mid teir board for a quality partner or you run a higher risk of things like this happening. Buy a cheap case, DVD writer, RAM, etc...There are places to save money and place not too!!! Sorry we could help you further...maybe you'll get lucky and someone else might have an idea but as for me I need more time and likely at a loss. I'll check back in soon.

 

[MCMunroe]

You should open Intel Extreme Tuning Utility
Check for two things:
Watch the CPU GHz while running Cinebench, see if it drops under max GHz.
Watch to see if you are having any VRM or Current limiting. They will flash Yellow.

 

[samuelbowater]

You should open Intel Extreme Tuning Utility
Check for two things:
Watch the CPU GHz while running Cinebench, see if it drops under max GHz.
Watch to see if you are having any VRM or Current limiting. They will flash Yellow.

I did what you said and the max GHz kept dropping to slightly below the max, but the VRM or Current were not flashing yellow.

Is there any way that my my PSU: VS 650(corsair) is the problem?

 

[MCMunroe]

If you watch XTU during the benchmark, or even check the graph after, you can see what is happening when the GHz dips, it will show if it is temps, current, TDP, etc. It really should show the correlation.

For example my EVGA FTW Z370 board, is well regarded but for some odd reason sets the BIOs Processor Core IccMax to 120A which is far too low and tends to limit the CPU to around 60W TDP. Easy to fix, but only from XTU.


Also not all CPU benchmarks or real world programs run full 100% load. If the load isn't constant, the GHz and Voltage will fluctuate. Cinebench tends to use all cores and have a good load; I see that you are using it. The XTU benchmark does loads that use from 1- more cores, so it doesn't load them up much.

Here is a screen of my system under a x265 load.

For reference my i7-8700k got a Cinebench score of 1579 with old 2400 speed ram, which is about 100 points less than Review sites. I understand that I won't reach review site scores with my mixed parts and desire for cool 24/7 load temps.