Ok, do you want to run a dual OS computer without the hassle of boot menus? Than this is the computer mod is for you. Two hard drives, some wire, some switches, and you can simplify a dual OS (Operating System) computer to!
I'm using the master/slave pins on the back of the hard drive in conjunction with a couple DPDT switches to "set" the OS before starting the computer. So each hard drive can be set Master or Slave from the front of the computer BEFORE turning the computer on.
Be sure not to flip the switches while the computer is running... could be a bad thing :D
Step 1: Mounting the switches
starting with a couple DPDT (Double Pull Double Through) switches. I mounted them on a unused 3.5 bay cover... but anywhere out of the way will work.