gigabyte ga p55 us3l is 64 bit supported? i have an old pc i5-750 , and this motherboard , i searched all over the internet and i cant find answer , i cant install windows 64 bit , it finds the hdd or the usb stick with windows 10 64 bit installation but it always says cant find operatin system on drive , but if i have a usb stick with windows 10 32 bit it runs perfectly , and hdd with windows 32 bit works fine also.