Question Does the ECS H81H3-M4(V1.0A) support GPT (GUID Partition Table) ?

What OS are you looking to at to work with that platform? Processor you're pairing with that motherboard? Asking with regards to the OS. Might also want to see if you've got UEFI on your BIOS before proceeding) and if you need to perform a BIOS update.
 
What OS are you looking to at to work with that platform? Processor you're pairing with that motherboard? Asking with regards to the OS. Might also want to see if you've got UEFI on your BIOS before proceeding) and if you need to perform a BIOS update.
there are UEFI and Legacy options under boot mode select. and also my bios have GUI