It's not power dip, it's voltage dip. An appliance will often draw the same power at the lower voltage, so increase current, which can cause overheating and damage.
Typically in these dip situations, you can hear the PSUs being very unhappy about the situation. A cringe inducing high pitched squeal can be heard from any PSU that's doing work as they try to continue doing their job while in this undervolt condition.
