I'm going to assume it was not possibly VRM temp related in your case.

I still have a couple that reach low 90 on occasion.
Those are still just sitting in some wind.

I mention that because it is certainly 'possible' that they got warmer I doubt it.

Some kind of clue is output from
cat /var/log/monitordcdc.log

It shows throttling of all die(on one ASIC) and documents cgminer restarts indirectly.
The timestamps have big jumps at 'events'.

Been runnin clean for a few hours now.
Pool thinks it did 3.7T for an hour!
3.600 would be perfect @ 500 and I had 2 die(or 6???) slower at the time.
It's just a calculating average wierdness when block times change during period averaged.
Still pool is not indicating anything to get alarmed about.

I'm just lettin it ride. It recoveres quickly.

YMMV