[ashenfang]

well here is my first attempt at a duct mod. I turned my 80mm exaust fan around to make it an intake and used dryer vent duct for the actual duct part. I left my processor fan on it because both fans have an approx. the same CFM rating. Anyway, My temps have only dropped about 1-2 degrees C, but I believe this is partly due to the fact that the intake in the back is close to the hot air exaust of the PSU. I think to make this effective and tubing of some sort will need to be added externally to drop down below the case to extract even cooler air.
Pics:

http://home.insightbb.com/~campbellmb/DSC00037.JPG

[AcEmAsTr]

cool, dont the ripples in the tubing obstruct the air flow?

[ashenfang]

no, not to bad, or not enough to notice, i was thinking, would i get better results if i reverse my fans? i.e. suck heat from the HS, and blow out with the exaust?

[chasingapple]

Might cause a bit of turbulance yes.

[heerboths]

well you might have a problem with the ridges in the tubing, you might want to try using a hose you can get from any auto supply store that does not flex as much. also could I recommend using your side case fan instead of your rear case fan to force air onto your cpu so the psu is not effecting the rear fan.

[schismspeak]

yes, the best fan to use would most likely be the side fan and have it blow into the tubing and use your rear fan as the exhaust.

[Joe_Atlanta]

Good job. With the rising ambients we are all looking to nibble 2, 3, 4 or more degrees away from our cpu temps.

Rather than adding more duct (and further airflow restriction) to the inlet side, why not deflect the power supply exhaust upward? A 4 to 6 inch plastic bowl cut in half does the job nicely.

[schismspeak]

I did not mean add more ducting, I meant just switch it to the side fan instead of the rear.

[Puer Aeternus]

The ridges in the tube can be a good thing...I have a duct w/ dryer hose and it has ridges...many moons ago I posted my pics and got feed back. There are diff views on this but riges actually help. I believe it dapens sound and helps airflow(someone back me up quick )
Anyway..I love my duct and after much experimenting I use only one fan. I have the duct leading to the front of my case and covered it w/ fine mesh to keep the dust bunnies at bay. The other end hooks onto my Ttv7+ and this fun sucks the air in. I tried using two fans and found that the temp diff is better w/ one fan....sides, 2 fans are noisier. Now Ashenfang, you may wanna move your tube to a front bay and leave that exhaust fan in place. I find that the duct cools the cpu and only the cpu..so consideration must be made for the rest of the case, IE: intake and proper exhaust to keep your pci/agp slots cool and HD's too. A good duct will give 5c+ temp drop! So be brave and fiddle until you find a setting that is right for you. I like Scismspeaks idea. this will move your tube away from the exhaust and improve airflow but sacrifice your vid cards cooling. I thing that hooking the tube to a front bay or the lower front intake fan (if there is room for that huge duct of yours) will clean things up a little.
BTW...Pics look nice....I think you can get better temps w/ that

[Joe_Atlanta]

Originally posted by schismspeak
I did not mean add more ducting, I meant just switch it to the side fan instead of the rear.

Actually schism, although my post follows yours, I was addressing it to ashenfang. Thought that was clear when I said "good job". I guess I should have quoted the relevant part in my first post. Sorry for the confusion.

[davidw11]

Looks neat...I don't have enough cooling!

[rogerdugans]

Looks good I like the silver duct as opposed the the white vinyl dryer hose I use

Two comments:
1) using the side fan for the duct inlet would gain you two things- away from psu exhaust, hence cooler intake air and it will continue to remove hot cpu air form the rear exhaust again.

2) Wiring- from the pic it looks as though your wires- which are well covered and tidy- still extend into the center of the case possibly obstructing airflow. If you can route those (or as many as possible) against the back panel/top of the case airflow across the board/ram/drives may improve.

Airflow is funny and it can be tough to figure out what WILL be best without trying different things; my comments are from what I have found [B]usually[B] works best- your mileage may vary.

In any case, a degree or two cooler is always good

[whiteemcee]

looks good, but looks very cramped in there.. maybe try and organize some wires and move the duct to the side fan would help your temps greatly ... just an idea..