You need at least 8.4GB disk space to install Ubuntu. This computer has only 0.0 B

Having trouble installing Ubuntu 16.4. When I put the disk in to install, I get the following message: You need at least 8.4GB disk space to install Ubuntu. This computer has only 0.0B I tried to use gparted to delete the partition, but I was unable to delete it. The partition only shows 418mib. The harddrive is seagate 500gb During start up I get this message: Radeon invalid ROM content. Any ideas how to address this problem. I can only access a terminal through try Ubuntu on the very first installation screen. I am a newby.