Comment 3 for bug 1530252

Something is strange in your system: on normal boot, you say i8kmon controls system temperature with fan turned on at 70° due your threshold, but on resume a default system control turns fan on before 70°C.

So I conclude that, on Dell Inspiron 15 3521, the default system for temp control does not turn on on normal boot, and only begins to work on resume from suspend.

Some more analysis needed! :-)