For those who aren't too familiar with the standard ATX case layout, the PC-V1100B back panel probably doesn't look unusual. Sitting the PC-V1100B next to a standard ATX case would make it look like it was upside down. Normally the power supply resides at the top of the case and the slots would be on the lower left of the case. To try and improve airflow, Lian-Li has modified the ATX case layout more like the BTX designs. In order to move the power supply to the bottom, the motherboard is flipped as well repositioning the slots and vent fan.
The lower power supply slot is held in place by four screws. Removing these screws lets to plate come off the case so the power supply can be attached. Once attached the power supply can be slide back into the case. Orientation of the power supply is important. Any air intakes must be facing downward when installed.
Another item of note is the cover the resides over the 120mm exhaust fan that isn't quite clear in the photo. This cover diverts air in one of the four directions. The interior of the diverter is lined with a soft foam. This helps reduce the amount of noise that exits the case from the rear panel. It also slightly reduces the level or airflow due to its restricted size.
