depends on your hardwareHow do I find out which one I need to use?
UEFI Boot Mode is recommended for 7/8/9/100/200/300 Series CustoMac desktops and all UEFI capable systems.How do I find out which one I need to use?
UEFIIs Rampage IV Gene with X79 Chipset UEFI or Legacy?
Spec says UEFIB75 LX motherboard uefi or legacy