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Zeroed85
04-13-2021, 07:31 AM
I'm seeing strange behavior running the 10900K in manual override mode with the XIII Hero. When I apply load to the CPU (such as Cinebench) the CPU down volts (according to HWiNFO). The voltage reading in CPU-Z is at odds with HWiNFO. When the CPU becomes idle again the voltage swings back to the manual override voltage I have set in the BIOS. I cannot figure out what is going on. :confused:

88344

EncodeGR
04-13-2021, 08:00 AM
I'm seeing strange behavior running the 10900K in manual override mode with the XIII Hero. When I apply load to the CPU (such as Cinebench) the CPU down volts (according to HWiNFO). The voltage reading in CPU-Z is at odds with HWiNFO. When the CPU becomes idle again the voltage swings back to the manual override voltage I have set in the BIOS. I cannot figure out what is going on. :confused:



Yes, that is the expected behaviour, it's what's called "VDroop".
The voltage drops while transitioning from "idle" to "under load". The lower your LLC (Load Line Calibration) setting is, the more VDroop you will have.

As long as you don't have any crazy drops or spikes and your CPU runs stable you don't need to worry about it. But that needs testing.
Otherwise, by increasing the LLC, you reduced those fluctuations, resulting in lower Vdroop and spikes, but your voltage will be higher overall.

Check the video below, it should answer all your questions:
https://www.youtube.com/watch?v=NMIh8dTdJwI

Zeroed85
04-13-2021, 08:16 AM
Yes, that is the expected behaviour, it's what's called "VDroop".
The voltage drops while transitioning from "idle" to "under load". The lower your LLC (Load Line Calibration) setting is, the more VDroop you will have.

As long as you don't have any crazy drops or spikes and your CPU runs stable you don't need to worry about it. But that needs testing.
Otherwise, by increasing the LLC, you reduced those fluctuations, resulting in lower Vdroop and spikes, but your voltage will be higher overall.

Check the video below, it should answer all your questions:
https://www.youtube.com/watch?v=NMIh8dTdJwI

1.172V isn't a crazy drop? In the screenshot it's at 1.172V (5Ghz all core) running Cinebench R23... The average is 1.20V. This is with an LLC of 5... Asus Realbench is generating Cache L0 errors. So what do I do here? Increase LLC or the manual Vcore?

Why is CPU-Z not reporting the Vdroop like HWiNFO is? The voltage reading in CPU-Z is remaining static.

Zeroed85
04-13-2021, 08:35 AM
Here is the system idle, no CPU load, Windows balanced power plan. HWiNFO reads 1.288V (current) while CPU-Z reads 1.439V. The manual override I've set in the BIOS is 1.300V. So why is CPU-Z reporting 1.439V? Which program is reporting the correct voltage??

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Silent Scone@ROG
04-13-2021, 08:41 AM
The reported voltage will differ depending on the monitoring tool and whether VID is being reported or vcore. The VID is the voltage the CPU thinks it's receiving, Vcore is the real-time measurement. It's always preferable to increase Vcore rather than LLC when dialling in stability.

Cinebench is fairly current intensive hence the amount of vdroop present. Vcore monitoring on ASUS boards uses die sense which is a closer more accurate measuring point for CPU voltages under high current loads where impedances and resistance is present.

Zeroed85
04-13-2021, 09:07 AM
The reported voltage will differ depending on the monitoring tool and whether VID is being reported or vcore. The VID is the voltage the CPU thinks it's receiving, Vcore is the real-time measurement. It's always preferable to increase Vcore rather than LLC when dialling in stability.

Cinebench is fairly current intensive hence the amount of vdroop present. Vcore monitoring on ASUS boards uses die sense which is a closer more accurate measuring point for CPU voltages under high current loads where impedances and resistance is present.

If SVID is disabled in the BIOS will only vcore be reported or can software still detect SVID? I have SVID disabled which is making me curious as to why HWiNFO and CPU-Z report different voltages. I have the BIOS set to report die sense.