Over current behavior on server motherboards

I have a GPU with a missing VRM phase. I’m suspecting it causes brief spikes in current from over reacting to the drop caused by the missing phase. BUT, if that was the case, I’d suspect the system to stay off instead of switching on and off.
Obviously I’m looking into getting what’s needed to replace the phase.
The behavior just seems odd; “restore on AC power is disabled”.

My only guess would be that 5Vsb doesn’t turn off so the board doesn’t treat it like a loss of AC power and let’s the PSU turn back on as soon as it… “wants”.