Question System doesn't boot after adding an internal hard drive

Hi, I just found an old computer that I no longer used and I wanted to put it back together to use it as a server. I, therefore, needed to disable the 'halt on' option from the bios to be able to boot without having attached any external device, like screen and keyboard. I also had the operating system installed on a 120GB SSD and everything seemed to work perfectly. Then I added another 1TB internal hard-disk and now the pc is no longer able to boot the OS .. I did some troubleshooting for days but without coming to a solution. Does anyone know why the PC fails to boot and if there is a solution ??
Thanks
 
YOu'd at least need to jump into the BIOS (via Delete, Escape, whatever is required fro your mainboard early in the power on process), and /enter/examine the BOOT device order/priority tables to ensure the order still has your desired boot device at the top/listed first.
 
YOu'd at least need to jump into the BIOS (via Delete, Escape, whatever is required fro your mainboard early in the power on process), and /enter/examine the BOOT device order/priority tables to ensure the order still has your desired boot device at the top/listed first.
Obviously the ssd is the first field in boot priority and to be sure I also set that the pc cannot boot from the hdd.
 
ah, I forgot that the HHD is fully functional. Also doing other tests I noticed that if I try to boot with the HHD connected and the peripherals (monitor and keyboard) connected, everything works. The problem is that if I disconnect the peripherals and try to turn the PC off and on again I cannot boot, while if I disconnect the HHD I can. Very strange ahah.. pls help me