If you look really close at the door on the P80R you can just barely see the fans that located on the other side of the door.  The Lian Li P80R is the only case made that happens to have a total of three - 140mm fans mounted directly on the door, thus allowing it to pull massive amounts of air directly into the front of the case.  The air being pushed into the case will travel across all of the installed optical and hard drives that you may have installed in the 12-bays provided on the Lian Li P80R enclosure.

We could have shown you the rear of the enclosure with no gear installed but I think it is better to see what a case looks like with the gear already installed in the case.  The motherboard we have installed is a Foxconn 975X7AB with a Quad-Core 6600 processor and the the two Crossfire X video cards are a pair of Sapphire HD3870 1GB cards. The power supply is a Mushkin HP-580AP.  You can see that P80R has ten individual opening for graphics cards or any other card that you might want to place in it.  Lian Li has also added additional vent opening at the rear of the enclosure with one set at the very top and bottom of the case and another just above the card slot openings.

You will also notice that there are a four openings which will allow you to run water cooling tubing in and out of your case.

The door on the P80R can be place on either the left or right side which ever is your preference.  If you look closely at each of the drive bay covers you can see how the three 140mm fans are able to push the air directly into the case since the drive bay covers have a series of openings in them that allows air to pass through.  You can also see in the right-hand picture that the entire door has one filter that covers all three fans, in the event the filter gets dirty, and yes it will get dirty whether or not you have dogs or cats, just pull it out of it's rails and wash it with the sprayer on your kitchen sink.
 

Looking at the bottom of the case you can see the extra vent that we mentioned earlier and also notice that slot covers also have slits in them to allow the case to try and maintain a constant pressure.  Remember the key to a well cooled case is to allow as much air to leave the case as is being brought into it.  In our case with the three 140mm fans located on the front door of the case we will need to have the equivalent amount of air going out.  Currently we have three fans bringing air in and only three fans expelling air (rear 140mm and the top mounted 140mm fan and power supply 120mm fan) we then need to have enough vents to make up for difference we have.

At the top of the case you have the other vent we spoke about and vent on the back of the power supply where the 120mm on the bottom of the fan will help balance our air flow in and out of the case.  You can see that the top of the case is held on by two small metal screws so it a simple matter to remove them and take the top off the enclosure.  To install a power supply you are required to remove four thumbscrews which will release power supply mounting plate, then attach the power supply to the mounting plate and then slide the power supply into the opening and replace the four thumbscrews.