From DOS right? Go to Custom Test, run the Tests on ALL Devices, and select "Quick Tests Only", after the diags has run on all devices, select the "Errors" tab on the right hand side. If 0f00:65d occurs then it should show the error msg, which will tell you what it means. If you don't know what the msg means, post it here and I'll see if I can tell you what it means.
It means that your hard drive has failed.
Try running the full diagnostics and report back any error messages. How to Run the Dell™ Diagnostics Utility