cooling a PC system

[kbkatz]

I am considering purchasing a fan that runs off of a PCI slot. Are their any better case coolers or .... I'm open to suggestions.

[Floppyman]

I was considering one of these for a while too, the only downside is that you lose a pci slot. If you extra room in your case to mount fans I'd do that first, unless of course you want a fan in that spot to cool a peripheral card like a videocard. I suppose you could also mod your case and put on the side of it where the cards are. Hope this helps.

[kbkatz]

Thanks
I think that is what I'm going to go with

[Omletteboy]

I have a slot fan in my system and I it helps in cooling, even though warm air rises it's still increasing the air flow inside the case.

[morriswindgate]

The key to cooling is not just adding fans until the case sounds like a 747, the key is getting uniform air flow throughout the case and across the boards and components. Almost all cases use a system where they pull air in from the lower front and then exhaust it through the Power supply. This leads to a " reversed S type flow" which brings air flow across the CPU area, but leaves dead spots in the drive and PCI Card areas.
In the out of the box configuration, most cases operate in a negative pressure mode ( PSU Fan exhausting air and creating a vacuum which is relieved by pulling air in from the vent and openings in the case). A much better way to cool the computer is to overpressure the case. When you overpressure the case ideally you create uniformed pressure that is relieved by not only venting through the power supply, but also through the spaces left around dives and cards thus creating air flow along their surfaces. Too much pressure though will cause the air to virtually quit flowing while it tries to escape through the small openings. And as we all know no air flow across a high speed CPU is deadly. So air flow must be balanced to provide adequate/constant air flow across the components.
In addition to the above problems, the layout inside to case is a problem. IDE cables, PCI Cards,and Drives all create restrictions to uniform air flow by creating turbulence. What this means, is when you have turbulence you have areas where air is flowing slower (or not at all)than the surrounding air. When this happens the faster flowing air actually starts acting like an insulator to the stagnant air,keeping the heat in the low pressure area.
So after reading the above you have decided that the only solution is to remove the sides from your case. DON"T! If you remove the sides from your case you actually aggravate the problem. Still air does not cool as well as flowing air. What you have done now is create a Spot Cooling situation. By this I mean that the Power Supply, CPU, and the Video card have air flow because of the active heatsink, but all the other components are reduced to natural convection for their cooling and will run hotter.
So what do you do?
OVERPRESSURE THE CASE, but instead of using one large fan, use several smaller fans directing their air flow onto or over components. Next get some of the round IDE and Floppy drive cables. Use tie wraps to arrange the cables into small bundles (as few of these as possible without putting strain on the
connectors).
I use a combination of fans and small squirrel cage blowers ( These blowers allow you direct the air flow and do not produce turbulence like tube fans)
For round IDE cables http://www.cables.cc/
For blowers Radio Shack or from Http://www.jameco.com (item#134586)
For More Info on cooling http://www.tweak3d.net/ (left side under TWEAK Guides "Air Flow Guide"