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Newer PSUs with 2 fans
RitualOfTheTrout - Oct 13, 2004
  RitualOfTheTrout Oct 13, 2004
Im sure everyone has come across the newer PSUs with 2 fans. They have the typical exhaust fan in the back, but they also have another one. My question is if you were to install that into a case would you need to cut a whole in the top of the case for this fan?

Here is a link for one at New Egg that I was interested in New Egg PSU...

 it290 Oct 13, 2004
Um, I think that power supply is simply photographed upside down to show that it has another fan. It takes air from the inside of the case and blows it outward. I've never seen one where there is a fan on the top, nor would that make much sense.

 Alexvrb Oct 13, 2004
As he said, that goes on the bottom of the PSU and pulls air up into the PSU, where it is vented out the back. PSU fans, in addition to cooling the PSU itself, pull a lot of hot air from the case. In ATX and similar cases this is vital because they're housed in the top, where the heat will want to go. This is why many OEM boxes can squeak by without seperate case fans.

Oh also, a PSU being "new" doesn't necessarily mean it has two fans. Some of them are too cheap. Some don't need it. Some use one larger fan instead. I would take a single 120mm fan over two 80mm fans any day. Although some have one 80mm for the back, and a 120mm in the bottom.

As for opening a hole in the top of your case to vent out there... that's more for modders, and you wouldn't usually want two competing exit paths out of the PSU, so you might close up the back too. But that's still kind of stupid and only for hardcore case modders anyway. I think the time would be better spent ducting your CPU fan or some other interesting work.

 Quadriflax Oct 14, 2004
I was somewhat curious about the bottom fan on the PSU. As Alexvrb points out, that would just push hot air from the case over the PSU. How much heat is too much heat for a PSU? Or is this negligable?

I guess what I'm saying is, there seems to be better ways to get heat out of the case. The case... I'm looking at has a fan on the top already. It seems this would be a better way to vent air out since it wouldn't have to bypass anything on the way. In theory, at least. In practice it might not make any real difference.

 RitualOfTheTrout Oct 14, 2004
I would think that if the air inside your case was hot enough to damage the psu your PC would be in some serious trouble. But then again I could be wrong.

My case also has a fan on the top and I was planning on getting a window kit with the fan mount to replace that. Then I saw these PSUs with 2 fans and wondered if the bottom fan was actually supposed to suck cool air in from atop the case (requiring me to cut another hole in the top of the case) while the back one exhausted it or if it sucked in air from inside the case.

 Quadriflax Oct 14, 2004

  
	
	

		
		

			Originally posted by RitualOfTheTrout@Oct 14, 2004 @ 07:16 PM



My case also has a fan on the top and I was planning on getting a window kit with the fan mount to replace that. Then I saw these PSUs with 2 fans and wondered if the bottom fan was actually supposed to suck cool air in from atop the case (requiring me to cut another hole in the top of the case) while the back one exhausted it or if it sucked in air from inside the case.




[post=121017]Quoted post[/post]


Out of curiosity, how many fans do you have in your case? I currently have four (PSU, CPU, Video Card, Case), and it's not too loud. I ask because with that case I linked to I could add another three or four fans but I'm curious about the extra noise it would add. I've been thinking on and off about installing a water cooling system, limiting fan noise being one of the factors.

 Alexvrb Oct 14, 2004
PSUs generate, and can withstand, a good amount of heat. The idea behind the second fan is to draw a larger volume of heat out of both the case and the PSU. Basically, it helps cool everything. It's really no different from having one fan, because if you look at a PSU with only an 80mm fan on the back, the air still goes through the same places more or less. You just use a second fan and/or a larger fan to push more air through it.

Also, paint it blue. Blue makes it run cooler. Just like painting a car red adds horsepower.

 RitualOfTheTrout Oct 15, 2004
I have 4 case fans ( 1 on the side blowing in, 1 on top blowing in, and 2 in the back blowing out), PSU with one exhaust fan, the CPU fan, and I have a harddirve cooler that has to very small fans on it.

The main cause of noise I noticed from my case from fans was due to the guards not allowing enough air through. The fan cutouts on the back of my case seem to have more of the area blocked than open, so this reduces effciency of the fans and increases noise. I plan on cutting those out and replacing them with a less obstructive fan guard.

 it290 Oct 15, 2004
Maybe you should just consider eliminating some fans to reduce noise, heh. Unless you're doing some serious overclocking, 4 case fans is definitely overkill.

 lordofduct Oct 15, 2004
OVERKILL ROCKS



SIX FANS... overkill, for the overclock!

 Alexvrb Oct 15, 2004
I'm a fan of balanced, intelligently designed systems.

 Curtis Oct 16, 2004

  
	
	

		
		

			Originally posted by Alexvrb@Oct 15, 2004 @ 01:16 PM



I'm a fan


Yuk yuk.


  lordofduct Oct 16, 2004
well 4 of the fans are REALLY needed, such as the ones on the HD's... one of my HD's is kinda screwy and heats up alot for some reason. eh whatever. (dont ask me why, its maxtor thats all i know.) I need those two fans on the side for my over clocked vid card.... of course the PSU fan.

So after all that noise, i figured why just leave those 2 extra spots empty, whatever fill em' in.

 Alexvrb Oct 16, 2004
Hmm, you could always use quieter fans, but I take it you don't really care. I can't stand a noisy box.

It's not to late to take out all the fans and paint it blue!

 lordofduct Oct 18, 2004
It helps me sleep...

 RitualOfTheTrout Oct 18, 2004

  
	
	

		
		

			Originally posted by lordofduct@Oct 18, 2004 @ 08:31 AM



It helps me sleep...




[post=121256]Quoted post[/post]


Yes I agree, I have a hard time falling asleep without a fan blowing air on me all year round (Maybe why I have fan over kill on PC aswell ). The noise from my PC makes a low calming white noise which actually helps me sleep compared to absolute silence.

 Alexvrb Oct 19, 2004
I'm perfectly happy with the quiet ticking of a clock.