This wasn't helpful...

This wasn't helpful. I'm not using a RAID, and I only have one partition. I was getting this before, so decided to start from scratch, so i formated, reinstalled Snow Leopard from the iMac disc, ran updates, now i'm trying to install Mountain Lion and stuck here.

The only thing i can think is that the hard drive is bad, but i ran a check with the Disk Utility app, and says it's fine.

Help..?