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Journeyman III

My 3900x won't thermal throttle when manually overclocking (under volting). It will go all the way up to 105 degrees C when running Cinebench.


I had been noticing that my 3900x will use 1.5v at normal operation or auto overclocking.  To prevent degradation I decided to under volt to 1.3v.  After that I noticed that the processors would not boost past 4.0Ghz even at 1.5v, so I decided to manually tune the cores to 4.3Ghz.

However I notice that the processor will not step down the frequency when it hits the thermal limit of 95C.  It will go past 100c with no thermal throttling.

I even went into PBO to manually set a thermal limit of 95C but this did not work either.  

How can I fix this?

1 Reply

Open up Ryzen Master and click on settings.

In the advanced box there should be an option for PROCHOT.

Make sure this is enabled.

If it's already enabled reset your bios, reenable your memory XMP profile and then don't overclock until you get a better cooler.

Either way you need a better cooler.

Your cooler can't cope with the heat output of the CPU.

The Ryzen CPU's will limit maximum boost frequency as temperature rises until it reaches a steady stat.

This is why the CPU is limiting itself to 4GHz under normal operation.