We seem to be having an issue with the Dell 790 Optiplex. I have contacted dell but their solution hasn't fixed the issue. I have a ghost image for all machines which is on various Dell Machines here. The issue with the optiplex 790 is is sometimes when it boots you get a message "hard drive not found" and it causes the machine to try to repair itself which it can't. I've been able to use the disk and run a repair and sometimes that works. If not I just throw the image on it again. This is happening to machines that we've already repaired. Dell gave me firmware update which hasn't solved this issue. I'm not 100% sure what this issue is. We even tried installing from scratch just in case it was the image but this issue is the same. Has anyone had this issue and if so what did you do? I even ran diagnostics but that shows nothing.