Hi,
 
I thought I remembered that the vcore status led was lit on post. I recently noticed that on my bench the vcore status led is no longer lit. Its driving me crazy.
 
posts fine and vcore is reporting on prob-it and dbugport display.
 
I checked here https://xdevs.com/guide/e399ocg/#diagled for reference and did not find anything.
 
and on closer inspection I noticed that vcore led in the status led row is different than the other leds in both the marketing images and on my bench.

@TiN_EE
Thanks for chiming in.
 
I'm not sure specifically as to which tests. So I just RAN CB15 ~10 times, Prime95 with AVX for 30 minutes and pushed 220~watts through the 9900k with AIDA64FPU/CPU stability for ~15 minutes, the VCORE LED did not even blink.
 
This above testing was run at 5.2GHZ, RR47, 1.35V-1.40V Vcore
Peak temp 78c on an open bench - Chiller
 
Totally DARK heh.
Flashed BIOS from 1.03 to 103,1.04, 1.06 - Same behavior
Removed all power connectors from board - Same behavior
Switched to another Trident Z Bdie kit - Same behavior
 
Unfortunately I didn't have another 9 series intel cpu to test. I guess Ill order another 9900k and see what happens when it gets to my doorstep if still no vcore LED after that. I guess my next step is RMA Z390 Dark.
 
CPU shows no issues. CPU still Clocks to 5.4 @ 1.4v and passes CB15 just as before I noticed the vcore LED behavior.
 
To be clear. LED does not blink and is not dim. it is not lit as though no power however
DMM shows 3.33v on ram side of led and 1.96v on X side of LED -edge
 
the rest of the status leds show on DMM
2.54 on ram side and 0.00 on X  side - edge
 
 Edited to add that the dip in watts in image 2 is due to AIDA64Cache stability testing which I turned on and off during the stress test.

@TiN_EE
Sounds reasonable and stoic, unfortunately issues with obsessing on every detail working as it should will not allow me to ignore. Ordered another 9900K just to test and for peace of mind. I have big plans for this board and would regret getting all setup for a sub zero run only for this seemingly non issue to manifest as a bug when really pushing the hardware.
 
Do you mind sharing a full circuit diagram? If not how about redacting the super secret DDR related layout. I am really just interested in exactly how the Vcore LED gets its power and am time constrained with regards to RE'ing the circuitry.
 
@anyone else with a z390 Dark.
 
Could someone please check the voltage reads at both sides of the VCORE LED located in the status LED row near the ATX 24pin connector?
 
Also has anyone else experienced this behavior with the vcore LED not lighting up at all?
 
Thanks,

@tjohnston3
 
Thanks for info much appreciated. Now that I know I am not the only one. Maybe my subconscious just wanted a justification to purchase more 9900k. I tend to get a little weird after multiple late night OC sessions.
 
Still curious as to what the deal is with the voltage on each side of the LED.
 
 

That makes Vince the KN|GHT K|NGP|N
 
-- Shameless and timely Game of Thrones reference. In this exercise I will play Jon Snow who "knows nothing."
 
 
It would be the least time consuming and easier for me to purchase another CPU and observe the behavior of both CPU's on the Dark and another Z390 with a CPU V LED. Which is why another 9900k is arriving tomorrow. Ugh and now a ROG MAXIMUS XI APEX. THE HORROR...
 
Ill go purchase the Advanced RMA and extended warranty for my EVGA gear while i'm at it.
 
I appreciate your input and got a good laugh out of the previous response. Obvs im here to learn and am EVGA/TIN/K|NGP|N fan.
 
Zeddi