Different drives. It fails before even attempting to boot anything and all I get on screen is the Copyright American Trends notice and Press CTRL + P to enter MEBX setup or ESC to Startup Menu. The choice is acknowledged but neither option works goes anywhere when the 2nd drive is in.
I've tried formatting the drives with various options on Disk Utility on my Mac.
Machine is a HP Compaq Elite 8300 SFF so not exactly new. The PSU in theory has enough power.
Also when I stick in a unformatted drive, it works fine, it loads up, you can then use disk manager to initialise and format, add files etc and all is great, until you restart and then nowt.