CPU throttling to 0.3GHz at low temperatures

IrisCZ wrote:

Ever since I bought the 2020 MacBook Pro (i5@2GHz), I feel like fans were running much more often than they should've. Usually the laptop remains silent, but sometimes out of nowhere I get sudden spike in fan activity while temperatures of all component are absolutely fine (bellow 60C for CPU and GPU).

I've tried using Macs Fan Control to keep the fans at bay, but unfortunately the laptop instead of running fans starts to throttle like crazy, when I set the desired fan speed. However, the temps are completely fine as you can see on the graph bellow.

The MacBook is unusable while it's throttling, as it gets as low as 300MHz. I've already tried a complete reinstall of the macOS, both beta and stable builds as well as several SMC and PRAM resets without any change. I doubt the temperature sensors are at fault, because they all show similar temperatures.

I am honestly really thinking about selling the laptop, because it starts to become unusable for me due to the excessive noise when doing literally nothing but playing a video or browsing the web.

Does anybody know how to solve this issue?

https://discussions.apple.com/content/attachment/31ccaad9-f93c-45e7-b9e5-148816074978

Did you try running the Diagnostic...

the user Diagnostic...not as definitive as Apple's own AST2 (Apple Service Toolkit) back bench diagnostic, but may kick out an error code.

Use Apple Diagnostics to test your Mac

https://support.apple.com/en-us/HT202731

IrisCZ wrote:

So apparently nobody can help me. None of the official resellers in Czech Republic wants to accept the laptop for free repairs as there seems to be actually nothing wrong about it, despite them acknowledging that this behavior is not OK and the device is still under warranty.

Can anybody point me to a direction where I could get at least some help? If not, I guess I will have to sell the laptop in the end.

on line  https://getsupport.apple.com/

Unfortunately Apple has no way to detect and monitor these types of anomalies. Apple relies solely on their Apple service diagnostics so unless something shows up on the service diagnostics Apple will not do anything about the issue unless you can show a problem while using macOS (preferably while only using official Apple apps since Apple tends to ignore issues with third party apps mainly because there are too many unknowns with third party apps).

Maybe you can present your evidence to an Apple Authorized Service Provider instead (try all the ones in your area if necessary). Maybe you will get lucky and get a tech that is willing to use information from the Intel Power Gadget or other methods to figure out the cause. Most likely it will require the replacement of the Logic Board, but anything on the laptop could potentially interfere with the power to the system.

Make sure to disconnect all external devices since one of them may be causing the problem.

Unfortunately the screenshot of the Intel Power Gadget doesn't tell me a whole lot without knowing exactly what was running on laptop at the time. This is something that will likely need someone to physically perform tests & observations on the laptop. Does the issue happen when using just the battery? If it happens only when using the charger, then perhaps the I/O Board (aka USB-C ports are bad/damaged). A physical inspection of the USB-C ports should be done which can be very hard to do because it is extremely hard to see the contacts clearly (I've personally missed seeing minor corrosion on them until I've fully removed the I/O Boards from the laptops).

IrisCZ wrote:

Moreover it seems like it's possible for me to at least mitigate this issue a little bit by connecting the Thunderbolt cable to a different port and therefore a different bus.

This may indicate the connector on the one USB-C port is bad (or partially bad) since they should work the same (although I have seen reports that the ports on the left & right sides of four port models may have different behavior in maximum throughput).

Because it's not the only issue I have when connected only to this display (my bluetooth audio cuts off and delays itself sometimes when connected to this monitor), I suspect the problem is not in the laptop, but somewhere in the display. Also from what I've gathered from other posts on the internet after googling my issues, I am not the only one with these problems.

A partially bad USB-C port can sometimes cause odd issues if the bad port is not being used, but I also would not rule out the monitor. You may have more than one issue. These USB-C Macs can be very difficult to troubleshoot as they tend to have very odd behaviors compared to the older non-USB-C Macs.