Clevo sometimes does not load. What the reason?

Clevo P650RE. Work 7 years well.
Windows 7x64, original Clevo drivers.
VGA GTX 970 /6gB.
About 1year ago during the boot start a problem:
In a bottom of screen purple horizontal lines with thrilling.
And after desktop apear sometime work with distortion, sometime- black screen, and sometime - its gone(distortion) and i can use laptop.
I send to repair to "RMA service".
They diagose a VGA issue.
( 1st diagnostic)
In 2 weeks they sad:no, its not fixing a problem, this is VRAM. ( 2nd diagnosis ).
Then replase VRAM too.
Now, after RMA -all the same -ISSUE NOT FIXED.
Laptop not fixed.
And the company say: this is because the windows 7. Updating to windows 10 and drivers VGA -will fix it.
( 3rd diagnosis!)
This is for originally maden for windows 7 laptop?
So, the question for Sager/Clevo specialist: is the third (!) diagnosis correct?

 

Extra explaining: about 1 year laptop was work monthly without torn off. I was able play games in winow mode.
HDMI i never use. Try to connect to external monitor-no signal.
During the boot:always clear boot logo. The issue happened in a black windows 7 boot animation.
After the boot with issue i do torn off and boot again untill its boot correct.
Sometime 2-20 times.(may be less, but meny).
Also was try boot in power or in battery- dont see a difference.

 

Update: this is the video of issue i made in a client home.
Hope you understand, the first boot i am not record. I can not record each boot.

https://drive.google.com/file/d/1DlGQw_caklODq0TxRl2sfxN_Z57RQ7bZ/view?usp=drivesdk

 

One more record. Its about a week after RMA (a month from today):

https://drive.google.com/file/d/1DpfnxjkyILeuEqMTyiW9BUmcnwwBznCO/view?usp=drivesdk