CPU ratio drop and noise in speakers

[mochica]

Hello everybody,

I've just changed my graphic card and I'm having a CPU issue after that.

First of all here is my setup :
- I5-6600 with a cooler master on it
- ASUS Z170 PRO GAMING (updated bios with default settings)
- RX580
- PSU : 650 watts

After changing my graphic card, I noticed an improvment of FPS while i'm playing. Nevertheless, the FPS sometimes drop with no reason. At the same moment I hear some noise in my speakers (buzzz).

By monitoring my CPU I noticed that it was the reason of the FPS reduction.
Its frequency ratio deacreases spuriously in accordance with the symptomes (from 32 to 8 while few seconds). The temprature max of the CPU is 50°C so it doesn't look to be the issue.

Do anyone have an idea of what could be the root cause of my issue, or how to solve it ?

Thnaks in advance for you help

 

[anotherdrew]

CPUs will throttle due to heat, but will also throttle if the power limit is reached. The buzz in your speakers might also be due to a power issue. And you just added a GPU that draws a fair amount of power. Therefore, my first test would be to change the power supply. 650 Watt should be enough, but it might not be performing upto specs. If you have access to another power supply, I would try that first. If not, I would look for a retailer with a very generous return policy.

** This utility (https://downloadcenter.intel.com/download/24075/Intel-Extreme-Tuning-Utility-Intel-XTU-) should tell you if the CPU is power limit throttleing and I believe it is compatible with your CPU.

 

[mochica]

CPUs will throttle due to heat, but will also throttle if the power limit is reached. The buzz in your speakers might also be due to a power issue. And you just added a GPU that draws a fair amount of power. Therefore, my first test would be to change the power supply. 650 Watt should be enough, but it might not be performing upto specs. If you have access to another power supply, I would try that first. If not, I would look for a retailer with a very generous return policy.

** This utility (https://downloadcenter.intel.com/download/24075/Intel-Extreme-Tuning-Utility-Intel-XTU-) should tell you if the CPU is power limit throttleing and I believe it is compatible with your CPU.

Thanks for your answer, That was what i suspected also at first, but I'll try vith a friends PSU before considering changing mine.

Thank you for the software. No thermal, Power or currnet limit is throttling while the issue. In addition I tried a stress test with the software, and the CPU is stable and the noise doesn't occure while the test. As soon as I stop it, the buzz comes back...

It really looks like it's a miss management of the ratio with the CPU load...

 

[anotherdrew]

Most BIOS will allow you to turn off speedstep. This should lock the CPU in it's highest state. You should be able to do the same by changing the windows power profile to performance.

Another thought I had ... what if it is actually the GPU that is throttling (due to heat or power ... but only power explains the buzz). As the GPU drops in speed, the demand on the CPU is reduced and so the CPU reduces the frequency. This would explain why you see no issues when stress testing the CPU only. Just a thought. Let us know if the other PSU helps.

 

[mochica]

Most BIOS will allow you to turn off speedstep. This should lock the CPU in it's highest state. You should be able to do the same by changing the windows power profile to performance.

Another thought I had ... what if it is actually the GPU that is throttling (due to heat or power ... but only power explains the buzz). As the GPU drops in speed, the demand on the CPU is reduced and so the CPU reduces the frequency. This would explain why you see no issues when stress testing the CPU only. Just a thought. Let us know if the other PSU helps.

I disabled the speedstep and everything is fine now. Thanks a lot for your help and diagnistic. I'll still try with anouther PSU to be sure.

 

[anotherdrew]

I disabled the speedstep and everything is fine now. Thanks a lot for your help and diagnistic. I'll still try with anouther PSU to be sure.

One more thing to remember. By allowing the CPU to slow down you save electricity and the CPU builds up less heat. The hotter integrated circuits are, the shorter their life span. I'm not saying that it will burn out next week, but the CPU might last 8 years instead of 12. For most that is not an issue because it will be replace by then, but you should be aware of it. Also, if your power bill is a concern, you will have to be more diligent about turning off the computer when not in use. Again, it's not a huge issue (kinda like an extra 60W light left on), but you should be aware.