Hero X, please help me understand vcore displayed while OCing

[dante_afk]

Hey folks

I'm having trouble interpreting the voltage showing in windows after I setup my OC in bios.

Hero X
8700k
32gb DDR4 3800


My settings:
Multi 50x
CPU Cache 45x
MCE disabled
XMP enabled
AVX 0
Vcore 1.22 Manual (later offset/adaptive)
LLC 7

Monitoring with HWinfo, CPUz and Coretemp.

Now if I go into windows, the idle vcore is 1.45. After starting Prime 29.3, it drops to 1.36 - alright that's the LLC drop, however where are the 1.22v?

Now if I go down with the LLC to 4 or 5, I have to raise my vcore obviously to 1.31 to make it stable again, however the idle/load vcore display is the same as above.

I don't get it, thanks!

[Shamino]

do you mean you set vcore to "MANUAL" 1.22v and see this? or adaptive?

[Raja]

If you're seeing it after setting Adaptive, change the SVID behaviour setting to best case, or tune the IA AC/DC load lines (start at 0.01).

[dante_afk]

I'm using manual, can't get adaptive to work/I don't understand the results I'm getting with LLC and the adaptive/offset values I'm setting.
SVID is set to best case scenario.

Could someone ELI5 the LLC behaviour on the Hero X?

LLC 7 should have zero vdrop, right? I don't get it. I've set manual to 1.24. Then the idle vcore is 1.45, and the load in prime95 is .1.34 - wtf?
The lower I'd go with LLC, the higher the vdrop would be under load, correct? Which means, If i'd set LLC 4 or 3, I'd have o raise the manual vcore setting?


Yesterday I tried adaptive/offset and put it to -0.200. I was able to run prime 1344k with 1.68v but the temperatures hit 100, they were higher than benching with 1.34v. I'm confused AF.

I was able to run 1344k in prime with manual 1.26 and LLC7, which resulted in 1.34v under load - which tells me 5Ghz @ 1.34 is stable, right?
Then I lowered the manual vcore to 1.24, left everything else as it was, but the load was still 1.34 in HWmonitor, the prime run at 1344k failed. ??

It looks like no matter which voltage I set under manual (1.2, 1.24, 1.3), the vcore under load is always 1.34.

[Wolfdale]

Feels like everything related to voltages is utterly broken with those boards. I'm seeing the same on my z370-F Gaming. I have CPU Core/Cache voltage on "Manual" with 1.31v. Here's what I get at idle:

https://i.imgur.com/H7qrDyG.jpg
(Notice the 1.42+ VID on the first 6 rows of HWInfo)

Then it drops to ~1.33v at load:
https://i.imgur.com/s6ZXEiv.jpg

Furthermore:
-Issue #2
Selecting a x47 multiplier with "Adaptive" voltage of 1.25v results in ~1.45v when I load Windows.

-Issue #3
The 3 states for SVID (Best case | Typical | Worst case) don't seem to work either. I've never seen difference between those 3 regardless if I'm using Adaptive, Offset or Auto. The Vcore according to CPUz and HWInfo is always the same for the specified multiplier. And riduculously high too. As I stated on Issue #2 - it seems that setting x47 for example with 1.25v adaptive brings like 1.45v. I can actually make a few videos and upload them to Youtube.

[Crysto]

Wolfdale I saw a similar issue when I tried changing the IA AC/DC Load Line values from 0.01 (which I read in an ASUS Kaby Lake guide) back to Auto as I was seeing some core voltage droop under Prime95 small FFTs. I'd been using Adaptive voltage at 1.3v, and after booting saw 1.45+! Where previously it was right on target. Not sure how 'Auto' should result in that sort of voltage overshoot, but try 0.01 in both fields, possibly 2.10 if that doesn't work as I've heard that is 'Intel spec' for that value.

[Wolfdale]

@Crysto
Whoa, it seems you are right about that. Setting the Loadlines for AC/DC to 0.01 indeed fixed the Adaptive voltage. Now with 1.25v set in BIOS I'm seeing 1.248 Vcore in CPUz and HWiNFO64 and 1.240v 'SVID' on HWiNFO64. That's indeed A LOT better - it's not just better, it actually feels right. I have no idea why the default value (AUTO) overshoots that much. Someone might easily fry their CPU. I imagine someone trying 5GHz on 1.4v and actually booting at 1.65v instead. Someone really needs to address that in a future BIOS version and fix the default 'AUTO' AC/DC voltage. 🙂

The 3 SVID states (Best case | Typical | Worst case) are still not working, though.

[flacer]

Wolfdale wrote:
@Crysto
Whoa, it seems you are right about that. Setting the Loadlines for AC/DC to 0.01 indeed fixed the Adaptive voltage. Now with 1.25v set in BIOS I'm seeing 1.248 Vcore in CPUz and HWiNFO64 and 1.240v 'SVID' on HWiNFO64. That's indeed A LOT better - it's not just better, it actually feels right. I have no idea why the default value (AUTO) overshoots that much. Someone might easily fry their CPU. I imagine someone trying 5GHz on 1.4v and actually booting at 1.65v instead. Someone really needs to address that in a future BIOS version and fix the default 'AUTO' AC/DC voltage. 🙂

The 3 SVID states (Best case | Typical | Worst case) are still not working, though.

can you post the change in bios that you do ... I also have 8700k with Strix F

[Praz]

Hello

SVID control does work. The result is dependent on Intel's programmed voltage algorithms and correctly set associated BIOS settings. Voltage reported by software can be off 0.030V or more as well.

[dante_afk]

doing ac/dc to 0.01 does nothing for me.