Question Laptop Doesnt boot free dos

[jerichoo]

Hello
I have Clevo 170Rd laptop and i am trying to boot it to dos but no matter what i do screen stuck to cursor blink in left up corner

 

[SkyNetRising]

Check boot options in BIOS.
You're probably booting into UEFI mode.
Switch it to legacy/CSM.

 

[jerichoo]

Sir i did it, and didnt work
also i have tried creating bootable usb rufus, poweriso ,hptool didnt work
downloaded manually dos files and create bootable usb again didnt work
tried to format usb fat32 ,ntfs again didnt work
tried 6 different usb key no change
in bios i have tried every possible combination no change .

that problem started after i updated bios everything works perfectly except booting to dos