I don't get what you tried to tell with the video.
It would be interesting to know what happens while you are gaming and the frame rate becomes unstable or starts to stutter.
If you have two displays while gaming, you can watch on the second screen, how your GPU core clock (now 1275MHz) and temperature (now 85°C) change when stutter appears.
Same is possible for your CPU.
That's if the reason is temperature throttling.
In MSI Afterburner (should work for your card also i think) you can even see if the GPU is thermalthrottling or if it has a powerlimit..., and a nice graph of your clockspeed and temp. So you can see when throttling apears.
Other possibilities; does you laptop start things in the background? (antivirus software or something --> taskmanager: ssd or hdd activity, other processes on CPU...?)
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