This issue can be reproduced easily by running CUDA load in hybrid mode on an optimus laptop, just watch the GPU temperature reaches 75C, and it throttles to the lowest power state.
The new -gtt --gpu-target-temp option since 460 drivers in nvidia-smi controls the temperature which GPU thermal throttle will occur in degree celsius. However, the value is immutable for most laptop GPUs, and while they are immutable, this value seems defaulted at 75C and not ignored by the GPU, reducing the clock and memory frequency to the lowest power state when GPU temperature reaches 75C. Laptop GPUs are hence throttled way too early in their healthy operating temperature of 75C, with fan profiles of laptops that barely spin up the fans at 75C, GPUs affected by this issue can only operate at high performance for a short time period by manually setting to max fan speed, otherwise they spend most of time in a loop of scaling up to higher power state, and then throttled until cooled down to 60C.
I’ve tested 2 laptops, one is Acer Triton 300 with 2070 max-q, another is Asus Zephyrus S with 2080 max-q, both exhibits this “feature”. According to GreenWithEnvy readings, 2070 of Triton 300 has critical temperature of 87C, slow down at 93C and shut down at 98C defined in VBIOS, yet it throttles to lowest power state at 75C with 460 or later drivers. 2080 of Zephyrus S does similarly.
I’ve bisected driver versions which the last good version that throttles correctly according to VBIOS definitions is 455.45.01, any 460 and later drivers throttles way too early at 75C. According to the changelogs, the first release of 460 driver introduces -gtt --gpu-target-temp controllable by nvidia-smi, and this issues begins from there, hence I’m quite sure that this new feature is related to the described incorrect throttling behavior.