Im assuming your using this case. I see it already has 2 fans, one in the front, and one on the back, the one in the front is intake, the one on the back, is exhaust. I would actually keep those right where theyre at. It looks like the case also has one more on the bottom, I would place one there, and killer is correct, that should also be intake. It looks like there are two fan mounts on the top of the case. You can put both of these as exhaust, however, if you are using an aftermarket heatsink that relies on airflow moving to the side (such as this one) it may be benefecial to have the forward top airfan being intake, with the rear top fan being exhast. Every case is a little different, so it wouldn't hurt to do a little bit of experimentation there.
As for your fourth 140mm fan, for the side, the side fan is usually best used for graphics card cooling, and with a lower model card such as the 630, its probably not needed, but if you do, you can experiment with that on intake and exhaust, to see which works best.
As far as your fans are concerned, purchasing 4 140 mm fans would be a waste of money, there are only two (2) mounts on that case that will accomodate a 140 mm fan, the bottom one, and the side one, all the other fans and fan mounts are 120mm fans, including the front, the back, and both the top fan mounts. So you might what to change your order to 2 120 mm fans and 1 140, for 3 fans total, or 2 120 and 2 140 mm fans, if you want to use the side panel fan mount.
As far as fan brands, in my experience I have had the best luck with Rosewill fans, but Ive also used Antec and other brands and not had any issue with them.
Edited by the_patriot11, 14 April 2013 - 06:33 PM.
Primary system: Motherboard: ASUS M4A89GTD PRO/USB3, Processor: AMD Phenom II x4 945, Memory: 16 gigs of Patriot G2 DDR3 1600, Video: AMD Sapphire Nitro R9 380, Storage: 1 WD 500 gig HD, 1 Hitachi 500 gig HD, and Power supply: Coolermaster 750 watt, OS: Windows 10 64 bit.
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