CPU Frequency dropped when exporting video in Premiere

[NoobVigilante]

Hey guys, as you can see on the title you may understand part of my question now.

I'm doing my homework with my newly built PC, which has a R5 3600 and RX 5700 in it.

While I'm exporting the video in H.264 format, I found that the CPU frequency was dropping from the idle speed of around 3.9Ghz all the way down to 2Ghz, with the utilization of mere 50%.(p1)

 

When the export work was done, CPU went back to a boost clock of 3.9G. (p2)

 

That's very odd, since everything worked quite well in my old i5 machine. So I start a stress test in AIDA64, and found that everything was normal: all cores are in base clock and their temp. are around 70 degrees.

I searched on the Internet about my question but had no result.

I'm confused now so I wonder how to make the exporting process normal, at least the CPU should be fully used.

Perhaps I didn't express my question clearly since I'm not a native speaker, so ask for more info if needed. And you can ignore the strange Chinese characters in the screenshot, you guys are good enough to guess the meaning of them.

Thanks for answering my questions. Hi from China.

[porina]

I'd suggest downloading and running Ryzen Master and do another export. It shows various limiters, that might give a clue as to what is causing it to downclock.

[Juular]

It looks like it's throttling, either your 70°C readings are wrong (use Ryzen Master) or you've set too low thermal target in BIOS.

[Mark Kaine]

Well, your readings are most likely wrong,  Ryzen should be more like at 0.2GHz while idling too (under normal circumstances) 

 

As others have said use Ryzen Master to monitor this. 

33 minutes ago, NoobVigilante said:

Perhaps I didn't express my question clearly since I'm not a native speaker, so ask for more info if needed.

No, it's not quite clear to me, what is the actual issue,  does the export take longer than expected or are you just concerned about notoriously wrong frequency readings from Microsoft Windows 10 task manager? 

 

来自欧洲的你好 ~

 

[minibois]

How large have you set the pagefile? If you haven't done so, increase it to at least 8GB.

The users above have a bit better suggestions, but if that all checks out the pagefile size could be the issue.

[TetraSky]

Which motherboard do you have?

I had issues like this with my B450 motherboard. Updating the bios fixed it all for me so it's worth a try.

[Mark Kaine]

One thing that's definitely weird, when I decode or I guess export a video (is this what OP is doing?) my CPU is used like 99-100% constantly, so 55% like in this screen shot is definitely weird,  but I suppose that could be the program that's used to export since stress tests seemingly work normally?