Firmware mode dekak thamai Legacy & UEFI kiyanne :) oya deka change karanna puluwan BIOS walin.. Google it
Legacy kiyanne traditional BIOS walata.. Ekedi OS eka Boot wenne HDD eke MBR eka kiyawala..
UEFI kiyanne Updated BIOS. Ekedi OS eka Boot wenne HDD eke wenama hadapu EFI kiyana partition...