Actually, what I would do with that cabinet is slide the PS3 toward you and to the left (to within about an inch and a half of the left wall. Get a piece of cardboard, cut it so it basically just fits between the top and bottom of the compartment on the right side of the PS3 (again, about an inch and a half from the PS3) with about a 6-7 inch gap beween the back edge of the cardboard and the back of the cabinet. Put your fan in the gap between the cardboard and the right wall blowing out the front of the cabinet. This will pull the warm air from behind the PS3, basically doing the same job the PS3's own fan would do if the cabinet was open in the back.
Pulling the warm/hot air away from the back of the PS3 is more important than pushing more air toward the front of it. The PS3 will only take in as much air as the internal fan will pull.
So basically make a channel that creates a weak vacuum? Makes sense. And putting the fan facing the front wasn't to force more air into it, it was to keep fresh air in the cabinet.
Exactly. I had a desk that had a similar channel built into it for a PC (and even had a slot to install a USB-powered fan), because the desk sat flush against a wall, and it worked extremely well.
I figured that, but it's probably not really necessary, and may only make it harder for the warm air to be expelled from the cabinet since there is nowhere else for it to go. Turning it around and using it as an exaust fan in the set up I suggested would probably cool the PS3 more efficiently.
I didn't think it would work better than my previous set up but boy was i wrong. I played with it like this today for a good 4 1/2 hrs. and I couldn't even hear the fan in the PS3 going. The back of it was warm to the touch but it was blowing out relatively cool air the entire time!
I would not repeat WOULD NOT put a PS3, Xbox, PC, or any other type of gaming device inside a cabinet.
The issue you will eventually have is that your system won't have any air flow at all not that it has a lot in the first place.
I would have a separate table/wire rack to set your console on.
It might not cause any issues at first but over time that enclosed space will bake your system. Anything over 80 degrees outside the console and components on the inside can be well over the melting point for the lead free solder they still use on these systems.
I have 8 PS3's setting on a wire rack behind me, with several fans moving air across the rack. I keep the A/C below 75 degrees year round. While I haven't lost any PS3's I lost 14 Xbox's to red rings in out first 6 months. We made plexi glass end caps and installed fans on each level of the wire rack in order to keep the issues from coming back.
WIRE RACK SET UP
If you leave your system in that enclosed space when you play and it over heats you'll end up with YLOD or RLOD or a cooked hard drive or any other number of issues. The number 1 cause of heat related issues in these slim models are people placing their systems exactly where you have this one.