When does it throttle? I haven't noticed this.
What are you doing that causes your Apple TV to throttle? I’ve never experienced any of that behavior. It’s vastly overpowered then most media streaming devices.
The ATV4K3 throttles on games and some non-game apps such as Plex with HDR content. It is a known issue, but if you don't play a lot of games or use apps that are impacted then you would never know about the thermal throttling issue.
There are games that have better performance on the older ATV4K2 with A12 than on the newer ATV4K3 with the A15 due to the ATV4K3 not having a fan. MrMacRight on YouTube has some videos showing the differences.
Here is a screenshot from a system utility app on tvOS. Spelling aside, it only takes a few minutes of a graphically-demanding game to see it go from normal to high:
Not sure if Plex is still having issues, but the developer said they were working on a fix. The behavior is also present on the older ATV4K1 and ATV4K2, but the impact isn't noticed as the active cooling kept the device cool. The passively-cooled A15 in the ATV4K3 quickly becomes too hot.
With games, it can be really bad.
I keep a heatsink with built-in fan sitting on top of my ATV4K3. It looks ridiculous, but works great to keep the temps down enough to prevent thermal throttling for over an hour of playing games. The fan is plugged into a HomeKit smart plug, and I just tell Siri on my ATV to turn on the ATV fan when I start playing certain games.
Sad photo:
I bet you their issues is network related and have nothing to do with the device itself.
I can say with 100% certainty that the A15 in the ATV4K3 does thermal throttle, and it is not a not a networking issue.
When you play Wreckfest longer than 5 minutes on settings looking at least decent.
My experience with Wreckfest as well, sometimes in just a few minutes it becomes unplayable.
With the active-cooling heatsink that I use, I can get over an hour of playing with decent settings. I first tried a passive-cooled heatsink sitting on top of the ATV, and for Wreckfest, I could get about 10 minutes of playtime before thermal throttling. This prompt me to try one with a fan, and it improved things greatly.
Just sad that people had to resort to putting heatsinks on top of their ATV4K3.