I used a PC as a router/server machine. I bought it 8 years ago. And it didsn’t work well these months. So I’ve bought a new server. The model is HP ProLiant ML310e Gen8 v2.
I heard that it didn’t support UEFI but BIOS. So it cannot boot the big harddrives like 3TB HDDs without RAID as far as I saw on the net. But I found that small bios_grub partition on the head of the storage enable grub2 to boot from such big drives without RAID. So I put 1MB partition on my harddrive. So now I can boot Ubuntu Server 14.04.2 LTS.