SuperMicro h12ssl-i power led blinking

[teepee]

Hi,

I have a Supermicro H12SSL-i. It has been working for 6 months. Now when I connected it to power the LE1 led is blinking once every second.

This is weird since the manual (https://www.supermicro.com/manuals/motherboard/EPYC7000/MNL-2314.pdf) indicated that only two states are possible on or off. No mention of any blinking for LE1.

The LEDM1 is not showing any sign of activity and jumping the power button does not appear to do anything visible. There is no VGA output.

What might be the cause of the issue and further how to fix it?

Thank you.

[RageBone]

Have you changed anything in the recent times?
That includes having powered it off, or a power outage.

What revision is the H12?

Be aware that the H12 lineup uses some bare-silicon die voltage regulators that are very fragile and easy to kill.
Such dead regulators can and have caused what you are describing.

You will find a lot more info and experiences around those on STH.
This here is a thread, starting at page 4, linking to page 5 where it picks up on the issues i am describing.

H12SSL-I Stuck at "bmc initiating"

You could help us help you by posting pictures of the board and those ICs around the BMC, socket and between the pcie slots.
On newer revisions, SM moved those regulators to the back of the board.

[teepee]

Thank you for the reply. I will start going over the thread above.

I removed the motherboard from an old case (where it was working) to the table. The revision is “REV: 1.02” indicated by the text under Supermicro-logo.

Below is an image of the IC’s around BMC light:

and this is an image around LE1 (blinking):

[teepee]

Here is a picture of the backside of the motherboard under AST2500.

C67 (Bare-Silicon-Die 6 ball BGA DC-DC Voltage-Regulator?) is a bit scratched and like said it is the most probable cause for this problem.

I’ll do some measurements when I can to confirm this but as for now I think the case is closed. Is there any chance it could be replaced fairly easily?

[RageBone]

Seems like you got the newer revision with them on the back then.

The DC-DC converters are U4, U5 and U6.
Tiny silver squares.

C lettering usually indicates it being a Capacitor.
That C67 looks damaged is not that god, but not that deadly either.
Hard to say.

LE1 blinking and then stopping would mean that the board is at least receiving the standby power correctly and is able to verify the Bios and FW to be correct.

So not outright dead.