No rear exhaust fan

nineteenforty4 · 24 Aug 2013 at 21:34

Hey

I have a question, if the cpu is watercooled and the radiator for it is located in the top of the case with fans directing air up and out of the case past it, is it better to not have a rear exhaust than not.

Is the rear fan just going to be blowing cool air out the back and away from the radiator because there isn't a normal heatsink attached to the cpu?

Uncle Petey · 24 Aug 2013 at 23:30

It's not going to harm anything and is advisable if you have a GPU exhausting heat into the case.

Something Else · 24 Aug 2013 at 23:47

reverse it and have it as an intake?

better stick a dust filter on there though.

http://www.overclockers.co.uk/showproduct.php?prodid=CM-000-OE&groupid=701&catid=1428&subcat=2363

sneakysnail · 24 Aug 2013 at 23:50

How many intake fans do you have? having 1 intake and 2 exhaust fans at the back and top of the case would actually be worse for the cpu temps than if you have just the single fan exhausting through the radiator. If the rear exhaust fans not to powerful you could always reverse it and have it as an intake pulling cool air in to case that will get pulled up into the radiator

Uncle Petey · 24 Aug 2013 at 23:52

lol, I probably should've mentioned that since I run a filtered rear intake

Hakanese · 25 Aug 2013 at 00:15

I'm a big fan of airflow over the mobo regardless of how the cpu is cooled

Something Else · 25 Aug 2013 at 00:55

Hakanese said:
I'm a big fan of airflow over the mobo regardless of how the cpu is cooled

pun intended?

Hakanese · 25 Aug 2013 at 01:10

maybe..

nineteenforty4 · 25 Aug 2013 at 02:47

sneakysnail said:
How many intake fans do you have?

It would be two 120mm front intake, a 140mm bottom intake and two 140mm top exhaust.

Uncle Petey said:
It's not going to harm anything and is advisable if you have a GPU exhausting heat into the case.

Yes there is a gpu, but I'm not sure if the rear fans would be taking out hot air or cool air plus it could disrupt flow being so close to the two 140s on the top

Uncle Petey · 25 Aug 2013 at 03:08

Try it and see if you notice any difference.

sneakysnail · 25 Aug 2013 at 12:31

nineteenforty4 said:
It would be two 120mm front intake, a 140mm bottom intake and two 140mm top exhaust.

Yes there is a gpu, but I'm not sure if the rear fans would be taking out hot air or cool air plus it could disrupt flow being so close to the two 140s on the top

you could always reverse the flow of the case and have the 2 rad fans as intake fans blowing cool air into the case and radiator which would lower cpu temps a couple degrees maybe. The rear and bottom fans could also be used as intake and then use the two front fans as exhaust fans

PieEater · 25 Aug 2013 at 13:25

sneakysnail said:
you could always reverse the flow of the case and have the 2 rad fans as intake fans blowing cool air into the case and radiator

Pretty sure that would have the effect of making the case warmer as you'd be drawing heated air from the radiator directly into the case.

When positioning fans I personally go on the principle that hot air rises, so I have exhausts at the top of the case (roof and rear) and intakes on the bottom of the case (front and floor). With my air cooler I pretty much have a direct flow from the top front intake fan to the CPU cooler and then out of the case via the rear exhaust. The bottom front and floor fans provide cool air to my graphics card and any hot air that makes its way to the top of the case is pushed out via the roof fan.

In the OP's case I think having the rear as an intake would obviously provide a supply of cool air to the radiator but I think this would have the side effect of interfering with the rising hot air having a chance of being blown out of the case potentially leading to increased case and component temperatures. Having the rear as an exhaust should increase the flow of air out of the case potentially meaning that the air inside the case doesn't have so long to heat meaning cooler components and cooler air getting blown through the rad.