Apple Power Macintosh 7600/200 Series - Manual (Page 131)

You are now finished with the installation. You may reconnect the cables and
power cord you disconnected from your computer, turn on the computer, and
start using the equipment you installed.
If you need help reconnecting your cables, see Chapter 1, “Setting Up
Your Computer.”
WARNING Never turn on your computer unless all of its internal and
external parts are in place. Operating the computer when it is open or
missing parts can be dangerous, and can damage your computer.
131 Installing PCI Expansion Cards and Additional Memory