Try forcing it to a specific wattage. Configuration > Performance

In the auto tuning section, enable thay and force power target to 800. Save and restart bosminer. Make sure to give it time to tune to "stable". (On your dashboard, tuner status is at the bottom of the page)

After it's stable at 800, check your fan rpms and chip temp. Force it to 1450 watts next and check the fan speeds and chip temp once tuning is stable.