Found the air leak.
My setup is a negative pressure case. There's 3 120mm exhaust fans and a 120mm wide by 240mm tall filtered intake which is assited by 2 120mm fans inside the case.These were mounted to the inside wall of the hard drive bays.
Oviously the asssit fans didn't do any good so I decided to take them out. I came to this conclusion when I noticed the blades were not dirty as the rest of the fans and the heat sink were. Matter of fact the intake side of the fans were clean. It was the exhaust side that had a little dirt on the blades but nothing to write home about. So they had to go.
I stood the case up and took of the back side panel and you could have floored me with a feather. Nasty was not the word for it. As you can see in the photos, I didn't tape up this vent as I thought the flat wire would do that instead.
I was wrong.
This is where the nasty air was coming in. I've already cleaned up the vent and plan to plug it up with either duct tape on the inside or run a strip of white double side tape from the outside. There's not really enough flat spots in the inside of the vent to let duct tape stick securely so I'm leaning toward the double sticky on the outside. Besides in a low pressure enviroment, the tape may get sucked off and be self defeating.
The molex connector cable was in there to start with when I first put the computer together. The Antec P280 case comes with 3 120mm 3 speed fans The power hub was on the back of the case near the top on the inside. The 3 speed switches were on an adaptor and mounted from the inside facing out. They were a joke. The top speed could not keep up with the heat. So when I swapped out the CPU heat sink, they went also. Any way the cable was there to power the hub. When I installed the front assit fans it was convientant to power them from that cable.
So now that it's no longer needed, and thanks to a modular power supply, I can remove it from the case and put it away for future use.
Now let me come back to this picture to expand on something I saw. Better yet didn't see.
This case has a filtered PSU air intake that's on the bottom of the case. The feet on the case are short so not much air can get to it. The fan runs silent meaning it only needs to rev up when it gets loaded up and the temperature rises. If it turns out to need more air to stay cool, I'll swap the case feet out for a set that is a little taller. Sunbeam, and not the iron maker, has some that will fit right in and glow. A little bling bling for my baby.
So I saw was just a little dirt around the plugs and a tiny amount on the four air notches in the upper back. I'm real happy to see just that small amount. What I didn't see is the two vents in the case on either side of the PSU crudded up. Amazingly enough they are clean. When I get all the leaks plugged up these will need to be plugged up also.
So What do you do to your case to make it work better and keep the goodies cool?