Sooo true.....
and make sure they are set to blow OUT of the case, rather than suck IN....
unless they are at the front, in which case, suck in is correct....you can have them both ways on the top, since hot air rises anyway, and sucking in cool air at the top is usualy good for tyhe prosesor...
also, if you can stand the noise and are in dire need but cant get out/afford a new fan or two...a desktop room fan, with occilate turned off can be a godsend ^^
acording to some poll, if you have a desktop fan running next to your PC, your an overclocker ^^ pfff, i have but its cause i stuck my fan on suck when at the back and i cant open it for a while to turn it to blow lol
another thing...
processors...check regualrly that they arent gunked up...i once got 16 degrees drop temparature and fixed the rebooting/crashing of a machine, simply by cleaning out the gank in the heatsink...
vid cards....the same can be said of the fans on the vidcards. also, make sure yours (if it has a fan and not a heatsink) has got no busted bearings. the fans that get busted bearinfs are hard to turn with your finger and can make auful rackets starting up. this means your fan is on the way out, btw, so if its possible to change the fan or get a replacemnt, i would do so as soon as you can...i know this cause i have lost 3 vid cards over the years i have had PCs, all 3 to busted bearings causing the card to heatdeath ofer too little cooling
and remember.....if your sitting there in the winter with 3 coats on, your PC is a happy bunny ^^
unless you have a problem with the cold, slap on a jumper or a sweater, but leave your central heating off for the room, it not only makes dust out of you, but the heat costs you cash and its bad for your pc