Lockup issues...help please

[-=KaTcH(13)=-]

Everytime I try and access one of my storage hdd's (hdd's that is for storage only, no os installed) my computer locks up, and reboots on it's own. When I try and access them and copy to and from them when I am in safe mode however, the lockup issue does not occur. Anyone have any insight on what could be causing this?