Thinker i35 suddenly turn rainbow screen

My Thinker i35 keeps turning into rainbow screen after just a bit of usage

I removed the installed M.2 SSD and booted from a USB Live Ubuntu thumb drive and the same thing happens

The same thing happens if I booted from a USB Live Android thumb drive

The exact point at which the rainbow screen appears may vary slightly from occasion to occasion

It almost always appears at the point when I connect to the wifi

I just don’t know whether it is a BIOS or UEFI virus or a hardware problem

Any advice would be most appreciated, thank you

You can try an external monitor and see the output to judge whether it is a problem with the display screen or the display cable.

Yes I already tried that, when the laptop screen goes berserk, the external display does blank at the same time

So I think the LCD screen is fine

Anyone knows where I can download the original BIOS and re-flash it?  These are the details of the BIOS:

Aptio Setup Utility – 2017 American Megatrends
Version 2.18.1263

BIOS information
BIOS Vendor: American Megatrends
Core version: 5.12
Compliancy: UEFI 2.5; PI 1.4
Project Version: 3BANR 0.03 X64
Build number: 0000
Build Date and Time: 03/31/2017 17:02:04
Access Level: Administrator

Board information
Board ID: i35
Fab ID: Default string
LAN PHY Revision: N/A

Processor information
Name: Kabylake ULX
Type: Intel(R) Core(TM) m3-7Y30 CPU @ 1.00GHz
Speed: 1600 MHz
ID: 0X806E9
Stepping: H0/J0
Package: Not Implemented Yet
Number of Processors: 2Core(s) / 4Thread(s)
Microcode Revision: 3A
GT Info: GT2 (0X591E)

EC FW Version: 01.0A.2C
MRD PD Version: 03
ME FW Version: 11.6.0.1121
ME Firmware SKU: Consumer SKU
Sensor Hub FW: N/A