When I boot into the live CD, I can see sda. I can partition it with fdisk. But when I start the installer and it gets to the partitioning window, the "Device for boot loader installation" drop down box has only the usb disk (sdb) in it -- not sda. So I can not choose a place to install ubuntu.
What could cause that?
I am building two similar machines. The other one did not have this problem. The only difference is that they have different hard disks.
Update: originally, the drive had a centos install. I ran fdisk only after the installer did not recognize it. I just ran garted and this time I had it recreate the partition table and now the installer sees the drive.