i wanna put linux on a third hard drive in my 1,1 mac pro. i have a pc gtx 650 so startup manager is not an opoption. does linux show up in the os x startup disk menu in system prefs. or would i need a third party utility planning on installing arch linux in case anyone is wondering. i have my 1tb drive running el capitan a second one running windows 7 64bit and the 250gb that the bay seller included will be my linux drive thank u all in advance.