Fan starts running when playing YouTube video

[impulse462]

Have you tried your old computers connected to the 4K display and seen what happens?

 

[project_2501]

Have you tried your old computers connected to the 4K display and seen what happens?

My 2015 MBP were fine.
My 5yr+ old £500 cheap ThinkPad was fine.

 

[impulse462]

My 2015 MBP were fine.
My 5yr+ old £500 cheap ThinkPad was fine.

Yeah I know. I can play this stuff on my 2017 15” so curious maybe it’s somethig with the 13”? Not sure what the temps are with that computer.

 

[Ollifi]

I don't have the Air anymore. If I unplug the display, I can play 4K without the fans spinning too loud. 15" has dedicated GPU, 13" does not so that is probably the reason.

 

[project_2501]

I don't have the Air anymore. If I unplug the display, I can play 4K without the fans spinning too loud. 15" has dedicated GPU, 13" does not so that is probably the reason.

my 2015 13"without discrete GPU was fine
my cheapthinkpad from 5+ years ego with no discrete GPU is fine
the problems for me is related to the 16/17 models

 

[EugW]

Sure you're not getting a 4K video with the 4K screen? You'd be getting VP9 encoded video, which Apple for some anti competitive reason won't support for hardware acceleration (even though the hardware is able to it). It tries to CPU decode it in chrome/firefox. Safari get limited to 1080 h264 codec, therefore no issues.

For Chrome it's VP9 regardless of the resolution. 1080p would also be VP9, not just 4K. This is all software decoded.

For Safari it's h.264, and it's hardware decoded (low CPU usage). Also the limit is 1440p for h.264, not 1080p.

After getting a 4K display (which is plugged via usb-c dock), the fans of my MBP start running at highest speed possible when I play a 1080p video from YouTube. Computer also gets warm and the video doesn't play smoothly. This issue does not occur on Safari, but occurs on Chrome and Firefox. I have tried disabling hardware acceleration without success. Any advice? Thanks a lot.

MBP 13" 2017 TB
RAM: 16 GB
the entry-level i5 CPU
latest updates installed

Disabling hardware acceleration would mean you'd get the same issue in Safari too.

The solution is to stick with Safari when possible, and to leave hardware acceleration intact.