elscorcho, I think first we need to understand the problem, then address it. Please DL, install Ryzen Master (RM) and post a screenshot. RM is the AMD reference to measure CPU temperature. All others should be suspect. Please post more complete specifications including OS version, cooler etc. If CX600 is a 600 Watt power supply that is probably not enough power. I started with an 1800X and used a 750 Watt supply. Here are your processor specifications:
Looks like it should throttle at 95C not 75 but we really do not know what the temperature really is. Enjoy, John.
Thank you for your answer. I'm on windows 10 and my cooler is an hyper 212 led turbo from cooler master.
I've done another test and it seems like it's doing fine for a moment but when it goes somewhere around 70 to 75 ° it starts to reduce it's frequency :
As for my PSU it is a 600 watts indeed, is that not enough ?
Here are my specs again :
MSI X370 Gaming plus
Hyper 212 Led turbo
Corsair ram 16 go 2666Mhz
Bios : 7A33V5D
Thanks, elscorcho. Looks fine to me. Your processor is rated to 95C, so you should be fine at 75 or even higher. I would get a little concerned above 90C or so. I do think your power supply is too small, but as long that you have no hangs or other problems, I would suggest you not be concerned. You probably do not have much head run for more or faster RAM, monster video card or OCing. I would suggest you keep an eye on it. Some PSs will top their advertised power at least some. Enjoy, John.