2019 15" i9 throttles below base clock during final cut renders

[AppleMyI]

Is this normal behavior and just showing how incredibly optimized fcpx is? I was rendering out different clips to export and noticed my i9/16gb/512/560x couldn't sustain base clock speeds. I have background rendering turned off and fans set to full blast.

Latest 10.4.8 installed.

 

[mmomega]

Yep.

I believe there was probably at least a dozen articles and video covering the thermals of the i9 MacBooks.
It happens on my 6 core MacBook, quadcore and my 15" i9.
I don't have the 16" which has better cooling. But I only do as little FCPX on the MacBook as possible just due to how warm it gets.

 

[AppleMyI]

thanks, wasn't sure whether I had a defective unit or not.

 

[leman]

I don’t see any throttling in your screenshot. It looks to me like a mainly GPU-driven workload. Both the utilization and the power draw of the CPU are very low. To sum it up: your CPU is not throttling, it is just not being used nearly as much as you suspect.

P.S. there was a spike of CPU activity in the middle, showing low-core utilization with high turbo boost. Again, looks to me like everything works just as it should.
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I believe there was probably at least a dozen articles and video covering the thermals of the i9 MacBooks.

A dozen of those complaining about thermals while not showing any evidence of throttling the only ones that actually show throttling behavior were early in the day when the MBP has a power management bug - it was fixed in less then two weeks but some people didn’t get the memo as it seems.

The 15” MBP performs within the official spec. The 16” performs above the spec. That’s about it.

 

[am2am]

I do confirm - FCP is not using all 8 cores to their full performance - at least with the type of work I do. I was surprised that my fans are not maxed during rendering/export (MBP16) but then verified CPU use and it was far from max. It was a nice surprise actually - working with 4k in FCP without fans maxed-out (MBP16 rules)

It really depends on type of source material and output codec you use.
When exporting with H.264 or HEVC 8-bit - dGPU (hardware accelerated) is busy and CPU is not that much loaded (30-60% max).
When you try to export HEVC-10 bit - it's a different story. You may test it - CPU utilisation will jump immediately.