Dell Precision T3400 (Late 2007) - Manual (Page 18)

18 Quick Reference Guide
Back View (Desktop Orientation)
1 card slots Access connectors for any installed PCI or PCI Express
cards.
NOTE: Check the documentation for cards to ensure that
you can accommodate them in your configuration. Some
cards that require more physical space and power (such
as PCI Express graphics cards) may restrict the use of
other cards.
2 power connector Insert the power cable.
3 voltage selection
switch See the safety instructions in the Product Information
Guide for more information.
NOTE: The voltage selection switch is available on the
375-W PSU only.
4 back panel connectors Plug serial, USB, and other devices into the
appropriate connector.
3 2
4
1