Throttling (TDP) and pefromance issue on Dell Inspiron 7567

Hello! Recently i have played AAA games (Witcher 3, Battlefield 4, Mirror's Edge: Catalyst and other) and i saw that framerate is too low (~30fps) even on medium settings without (or low) anit-aliasing, but everything was perfect about a month ago (50-60 fps on high settings without anti-alising until this moment).

Relying on similar issues and CPU-Z information, i think that it is proccessor throttling trouble.But why? Proccessor temperature isn't high enough. (50-70 degrees Celsius) The problem persists even with connected AC adapter, disabled battery boost and other "great" nvidia settings. Also it seemed to me that the cooling became quieter and it works only on the part of the full strength. (a few months ago cooling was really loud)

Can the problem be related with the windows 10 update?

Additional information:

My laptop configuration:

OS: Windows 10 (default)

CPU: Intel Core i5 7300HQ

GPU: NVIDIA GeForce GTX 1050 4GB

Memory: 8GB

Storage: 1TB (HDD+SSD)

Any ideas? >.>

Thank you everyone for helping with the issue!