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120mm fan on side blowing or sucking?

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Jun 14, 2001
Athens - Greece
I'm going to install a 120mm fan on the side of the pc case to cool down the expansion cards. should I let it blow fresh air in or suck the hot air out? and a second question: is a little positive pressure good for airflow? I've read so on many sites but I would appreciate your advice. thanks
You should postion it so it is blowing air over the PCI slots. I have the following set up;
1-120mm blowing in lower front
1-120mm on the side blowing in
1-120mm on the top sucking out hot air
1-92mm mid rear sucking out heat from video card
2-80mm top rear sucking out
I Storm 2 HDD cooler top front cooling hard drive.
This seems to work well, was noisey, but I installed a Diga Doc 8 to control the fan speeds.
Positive air pressure isn't necessarily good for airflow, but it is good for helping to keep dust out of your case. My input is that you should just experiment with your fans and see which one gets better results. If you are blowing in, you won't get very good results if you can't move that much air out. If you blow out, air will be sucked in from every crevice to fill the vacuum you would be creating
that's a nice setup Da Whip! many many fans! what are your temps? i mean ambient, case and cpu temp. i think i'll let the fan blow fresh air into cool the cards.
hey anarki_gr...you should have the fan blowing onto the cards, but it is a lot of air flow, my 120's are at 90cfm's...but anyways my mobo doesn't have on board sound, so i took out the 3 metal holes for the sound ports and the game port and a pci slot above the agp and i use them for vents, so the exhausts fans won't be trying to spin faster to suck it out....i got 120mm on the side blowing in, 120mm on top sucking out, 2 hard drive coolers with 3 20mm's each, and then a 42cfm system blowing blowing air out at video card and then an ultra 80mm and power supply sucking out in back, along with an 80mm on the bottom front of the case, no outside air yet though! :(
hope that helped ;-)
Thanks, it took some time w/ a Dremel and Band aids, but was worth the effort. The DigiDoc helps w/ the noise.
As to the temps, my system is in the basement which never gets above 65F, sometimes colder whwn the A/C is cranked. Therefore the case temp is normally mid to low 60's w/ the CPU temp at idle never higher than 24C. anarki_gr have some fun, but try not to bleed all over the case like I did.
120mm over the HSF

how much would it help if I had a 120mm with 138cfm, blowing straight on my hedge hog with delta 60mm with 38cfm?

would it help or just burn out my 60mm?