Thanks everyone for your replies. It helped me with my issue.
I got the Strike the F1 key but it was earlier in the POST where I found the key message.
It was something like Primary Drive 0 not found or something of that nature. This is a PowerEdge 1600sc that has only SCSI drives, no IDE drives.
I just went into the BIOS (F2) and disabled Drive 0. Boots fine now.
Yes this is very very helpful thread.
I've fixed my issue by disabling unused ports.
Many many thanks.