Rear fan orientation

Resident · 7 Jun 2013 at 15:42

Hey guys,

At the minute I have a Phantom 410 case with 6 Corsair fans (4 AF120, 2 SP120). I have 3 AFs as intake (2 front one floor), 1 AF (rear exhaust) & the SP120s in the roof exhausting through a H100i rad. The removable HDD cage has been removed.

Now in this hot weather I'm averaging 34-36°c whilst I'm just pottering on the PC (web-browsing, emails & general low load stuff) which is great but I can't help but wonder if I'd see any improvement if I turned the rear exhaust into an intake, feeding cool air directly into the path where the SPs take from.

Any thoughts?

Khazzer · 7 Jun 2013 at 15:51

Does your graphics card exhaust into the case or out the back?

Resident · 7 Jun 2013 at 16:00

Khazzer said:
Does your graphics card exhaust into the case or out the back?

Sort of both. The stock cooler just blows up onto the heatsink but with the airflow across it from the front intakes some heat gets blown out the back via the vented PCI slot covers.

BluD · 7 Jun 2013 at 17:13

Sounds like ya have it right, especially if ya your gpu and psu are venting warm air behind ya pc.

Something Else · 7 Jun 2013 at 17:20

BluD said:
Sounds like you have it right, especially if your gpu and psu are venting warm air behind your pc.

Fixed.

OP- Seeing as you have 2 fans exhausting in the roof I would turn the rear into an intake, it would blow some air across the radiator and help a little.

Also unless you have a blower type system like Titan has or most reference cards then the gpu will exhaust heat into the case.

NightSt@lk3r · 7 Jun 2013 at 17:31

Id leave it as is, turning the rear fan into an intake is just going to pull the warm air from your PSU and GPU back into the case.

Resident · 7 Jun 2013 at 17:40

NightSt@lk3r said:
Id leave it as is, turning the rear fan into an intake is just going to pull the warm air from your PSU and GPU back into the case.

My PSU is semi-passive and it's only ever spun up the fan (excluding POST) twice in the 6 months I've had it and it's fan-side up which means any heat generated is vented into the case unless it spins up.

I've just turned the fan round and I'll monitor the temps for this evening.

Khazzer · 7 Jun 2013 at 17:52

I would suggest leaving the rear fan venting, given that you have a fair bit of warm air to be vented, it should allow the radiator fans to work better in my view.

Resident · 7 Jun 2013 at 20:22

TBH it's been running as an intake for 3 hours and the temps are just the same :|

I'm going to disable it completely and see if having it on at all makes any difference.

Resident · 12 Jun 2013 at 17:22

Just to update this, I disabled the rear fan and over the course of a normal day's use I saw no discernible difference in temps

daveip · 12 Jun 2013 at 17:25

Did you see any difference to your CPU temps?

I have a rear fan intake into my Corsair 600T and have a triple rad at the top just so that it can get some air that's that bit more fresh, but given the amount of air that goes through the thing, I don't think it matters that much. I just prefer it that way for the +ve pressure I'll get from the system

Resident · 13 Jun 2013 at 14:18

daveip said:
Did you see any difference to your CPU temps?

I have a rear fan intake into my Corsair 600T and have a triple rad at the top just so that it can get some air that's that bit more fresh, but given the amount of air that goes through the thing, I don't think it matters that much. I just prefer it that way for the +ve pressure I'll get from the system

Not really. There was a 1° increase in delta temp with it turned off however my ambient during that test phase was 4-5°c higher than when I was testing the fan on intake/exhaust and I'd already decided that +/- 1.5°c as an error margin which it was within.

I've put mine back as exhaust and just set it to minimum speed on the controller. It just looks better since I can see it and it's an AF120.