Question about clock fluctuating on Rtx 2080 Ti.

I have a question.
I am using Rtx 2080 Ti Waterforce and 9900K and Corsair 850RmX.
ALL stock,no oc. Drivers up to date,Windows 10 1903v.
Few days ago ,when i run Fire Strike GPU test 1 on loop, i saw a clock dip from 1980mhz to 1570mhz for 1ms.
GPU LOAD not changed,it was 96%. Only gpu clock dip for a 1ms. I checked in logs,and during that gpu power drop to 58%.



I cant reproduce this. Second. Yesterday i run TimeSpy looped gpu test 1. Clock during 40 minutes was 1920-1970mhz with random power usage. But one time it dropped to 1800mhz. Is this normal?

Screens: 1920mhz:



And that 1800mhz for 1ms:



Of course its POWER LIMIT only in this test. So i guess its not faulty hardware somewhere? In games i dont had any once such drops in clock. It happened in 3dmark once only and i cant reproduce.

I know but that power drops from 95% to 45% for 1ms its not hardware related?

I mena when test is running is always 95-90% power usage, but sometimes it drops for ms1 to 45% or 58% which result in stutter etc. Is this hardware related or software?