[SOLVED] 3800x fan speed and temperature spikes

Gabriel87

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Sep 25, 2013
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Hello , i just bought a 3800x with a ROG Strix B450-F Gaming and i experience some odd behavior , the temps when idle is around 48-62 (jumping from 48->62) when i use default settings in bios , i tried some settings myself with undervolting but i'm not an expert in OC and fielding around the bios could someone advise me please
currently i have the stock fan , i will upgrade it soon , and the bios is up-to-date, and in the first 2 pics are the default settings from the bios. What should i change for a stable and acceptable temperature when idle without the spikes
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Hello , i just bought a 3800x with a ROG Strix B450-F Gaming and i experience some odd behavior , the temps when idle is around 48-62 (jumping from 48->62) when i use default settings in bios , i tried some settings myself with undervolting but i'm not an expert in OC and fielding around the bios could someone advise me please
currently i have the stock fan , i will upgrade it soon , and the bios is up-to-date, and in the first 2 pics are the default settings from the bios. What should i change for a stable and acceptable temperature when idle without the spikes

That's perfectly normal for Ryzen.

Ryzen likes to put cores into deep sleep as much as it can for energy efficiency. When doing that it has to boost a core to max...
Hello , i just bought a 3800x with a ROG Strix B450-F Gaming and i experience some odd behavior , the temps when idle is around 48-62 (jumping from 48->62) when i use default settings in bios , i tried some settings myself with undervolting but i'm not an expert in OC and fielding around the bios could someone advise me please
currently i have the stock fan , i will upgrade it soon , and the bios is up-to-date, and in the first 2 pics are the default settings from the bios. What should i change for a stable and acceptable temperature when idle without the spikes

That's perfectly normal for Ryzen.

Ryzen likes to put cores into deep sleep as much as it can for energy efficiency. When doing that it has to boost a core to max clock to get a task completed fast and put that core back to sleep. That means it's normal to see frequent high clock boosts even at idle.

Along with the high boost is a quick rise in voltage to as much as 1.5V, and an equally quick temp spike. They're very quick and go away just as quick and really add very little to the thermal state of the CPU. It's just like lighting a match in a room: the match is really hot, the room isn't.

This means looking at the instantaneous temperature is misleading; you have to look at an average temperature to see the true thermal state of the processor. Get HWInfo 64 and look at the CPU die(average) sensor readout, that will give you a much better idea of the thermal state of the processor.

Also, Ryzen is designed to go as high as 1.5V during those quick boosts to keep the CPU stable. Lowering volts can help when the board mfr. tweaked presets but be careful how much. Always use offsets to do it since fixing voltage (even if at what you think is lower) can lead to degradation if not done properly. It can also reduce performance since it's boosting depends on seeing BOTH thermal headroom and voltage headroom.

And better than stock cooling definitely helps, especially a 3800X. A cooler processor will boost longer before pulling back, that's the way the algorithm works. But it will do nothing to cool off those temp spikes... no more than turning up the air conditioner in your room will cool off the the lit match's temperature. But it will help control the AVERAGE temperature of the CPU.

To keep fans from also surging with each temp spike you have to use a profile that ignores the spikes. What I do for my 3700X is set a flat fan speed that's barely audible up to about 65C then start raising it from there. I don't let it get really high and annoying until about 80C.
 
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