I have installed 'Debian Linux 10 non-free live', and everything is running extremely fast, with secure boot.
It's like Every website was popped up just before I clicked with fully loaded page.
I've never experienced this kind of fastness before.

And then I have installed Mint linux with Ubuntu based distribution.

When I installed it, it asked me to enable 'insecure boot', it said that it is necessary.
I wondered that how can a program(ubuntu linux) change my CMOS setting, but I trusted it and approved it.

Then the problem happened, It ruined all my firmware.
I cannot get secure boot again no matter what I did on CMOS setting.
And everything is slow, The fastness of my PC has gone!!!
And many bugs, one of m.2 slot not detected, cpu fan nospin. on bios 7003.
It was working fine before on bios 7003.

I have flashed BIOS but no effect.
I have tried many BIOS flashes but can not get the full speed back again.

I have searched and found that
'Insecure boot' is related to 'mokutil' on linux.
But I have no further information.

They ruined my motherboard
How can I get back the state of motherboard when it was fresh.

There must be something remaining even if I flash BIOS or clear CMOS.

Need to do factory reset.

How can I do that?
May be this is important point of security and bug correcting.