cyrnel

The fans are pointing the correct direction, no? If you can't remember which pointed where, try both front and lower rear for intake and the rest (plus p/s) for exhaust. More intake (positive case pressure) makes for a cleaner case.

I thought that case had a duct for processor air intake? Might have been another version of the side panel. If not, try ducting an intake fan to a processor shroud. Cobble something from cereal box cardboard if you have to just to see if it makes enough difference to get serious.

Be careful about cable placement. Get them out of the way, without creating turbulence or interfering with important airstreams.

Edit: Another thing - are you sure the new fans are really moving more air? Compare an old and new. Make sure the new intake fans don't have thermal sensors or they'll never come up to speed.

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There are a vast number of people who are uninformed and heavily propagandized, but fundamentally decent. The propaganda that inundates them is effective when unchallenged, but much of it goes only skin deep. If they can be brought to raise questions and apply their decent instincts and basic intelligence, many people quickly escape the confines of the doctrinal system and are willing to do something to help others who are really suffering and oppressed." -Manufacturing Consent: Noam Chomsky and the Media, p. 195