2 different pcs 2 different issues. Help

[Gottboost]

So first is a i7 9700 on a asus z370-p prime, 16gb 3200mhz ram. Boots to bios no issues. But when I go to boot from usb to install Windows, Windows symbol appears then it blue screens with error Whea uncorrectable error.  I have tried different cpus, ram, ssds,psu. Also install Windows and put it into the pc, bluescreens at Windows logo. Same error.

 

 

Second pc, ryzen 5 2600, 16gb 3200mhz, msi b450i. So it will detect and display with a quadro k620, but when I put in any other gpu that requires 6 or 8pin power it won't detect it and the motherboard white vga light is on.. once again tried different cpus,ram,gpus,psu but still no luck. The board is fully updated.