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how much power does additional fans use?

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Jan 2, 2001
i have 7 fans in my box with a 300watt power supply. how much wattage does each fan use. how many can you keep adding before you use up all your power?


Usually the dissipation is marked on the fan. They range from 2 to 4 watts on average, except maybe very high volume types. So figure 4w each for worst case and you'll have a ballpark figure.
so with 3 periphials (voodoo5, soundblaster live, and an ethernet card), is 7 fans too much. how many more can i realistically add?
I have 16fans going and it's doing allright w/cheap compusa 300watt psu.

Six of them are the little antec 3fan/ea drive coolers lucky if those are 4watts per/set. Then 4/80mm 2/120mm 1/60mm 1/40mm 2/blorbs.
Also drawing are 2/HDD 1/CD 1/Zip 1/Nic 1/modem 1/PCI512 1/V5-5500 Tbird750@840
I wanted to add one of those cool lights but with my luck that would be the straw that breaks the camels back.
With that many peripherals in your box, I would think that 300w would be marginal..especialy when u factor in the extra watts consumed by the proc being clocked,and the cpu fan/s.
A lot of people don't consider p.s. when trying to clock, and fail thinking that their proc is a dud, when it could be the p.s.
As a matter of fact,I am planning to get a 450w on monday, and all I have in my box is 1 cd,1hdd,modem,sb live,and a great big alpha h.s. with two big fans.
Some might say it's overkill, but I want not to question the p.s.'s ability to give what I want.
Even in your situation 450w maybe o'kill but it certainly couldn't hurt.
I don't want to buy a new Fortron Source or PC P&C 350 Watter just yet. I'm gonna dig through my wall wart collection. With luck, I'll find one with 9-12 VDC output. I still haven't figured out an elegant way to connect extra case fans on side panels to main power inside the case. Why not wall wart 'em, externally? No connection probs, and no extra load on the PS. Perfect!
I have to agree with the power issue. I have a 800 thunderchicken pushing 1ghz. Now If i drop back down the clock multipler from 10 to 9, and raise the frontside bus to say 112 my system gets really screwy. Alot of games start locking up esp when using the cd. The temp issue is still stable, in fact it doesnt seem to climb 42 under full load. I have a 120mm fan on the front using a reostat to control the speed, an 80mm fan in the rear, a 25mm thin line on the alpha pep 66t. Add to this the abit kt7, NIC card, ge256 video card, 8gig 7200 rpm hd, soundblaster live, cd burner, cd rom, and a 3.5 floppy drive. Even with a 300watt ps I do believe with high end overclocking, esp with fsb factoring the ps is being overwhelmed. I am looking into a stronger ps, perhaps a 400 or 450. I will post the new results, all you ps upgraders do the same :)