Airflow question - change the rear exhaust to an intake?

Overread

Overread

Overread

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So I've got the current build and I'm wondering if I can improve the cooling a little by shifting the fan positions around. The photo below shows the current side and position/direction of the fans in my system.

Phanteks Enthoo Pro ATX Full Tower Case - standard setup (large fan on front, smaller fan on rear exhaust position)
1 x Arctic Liquid Freezer* II High Performance CPU Water Cooler - 360mm - set to vent up;



Intake on the front, exhaust on the back and top.
I'm wondering though, as the intake on the front has to go through the block of harddrives on the front, am I simply losing a lot of cooler air flow.
Would it be worth considering swapping the top fan around to an intake to bring in cool air to that region and then let the top be the only vent, or is that going to mess with the air flow in the main region that's generating heat.
 
If I'm looking at that right, I would say you're going to have a hard time getting a significantly better airflow setup there, not without making some sacrifices along the way.

With only the one intake at the front that's also partly blocked by the drives, you're not getting as much fresh air to the GPu and CPU; The CPU being under the AIO and the GPU behind the drives.

The AIO at the top means that you're either going to need to make the whole airflow pressure postive by turning them all into Intakes (It's fine by the way to do that) but this increases your CPU temps that the AIO is attached to. Or the rest of your setup is going to have a poor source of cooler air available to them (only the front fan Intake). But if you do turn the top fans to Intakes, it'll also have the air fighting the air from the GPU that's aimed largely upwards aswell. So you're likely to mess up your GPU and CPU temps from that, or keep the CPU temps around the same, but make worse the GPU temps.

Turning the rear fan from an Exhaust to an Intake is also unlikely to help with anything much except the CPU temps (as there's more cooler air that's drawn out through the rear most top Exhaust fan. But it'll unlikely to much else for your GPU temps.

I think given the older designs of the case in question, means what you have already might already be the better optimal fan setups already, even though it is a negative pressure setup. And if you truly want a better air setup, you're likely to need to grab a more modern case design.
 
Overread said:
So I've got the current build and I'm wondering if I can improve the cooling a little by shifting the fan positions around. The photo below shows the current side and position/direction of the fans in my system.

Phanteks Enthoo Pro ATX Full Tower Case - standard setup (large fan on front, smaller fan on rear exhaust position)
1 x Arctic Liquid Freezer* II High Performance CPU Water Cooler - 360mm - set to vent up;



Intake on the front, exhaust on the back and top.
I'm wondering though, as the intake on the front has to go through the block of harddrives on the front, am I simply losing a lot of cooler air flow.
Would it be worth considering swapping the top fan around to an intake to bring in cool air to that region and then let the top be the only vent, or is that going to mess with the air flow in the main region that's generating heat.
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I'm thinking your setup is wrong. you need to put more intake fans. Now you have 1 intake fan and 4 exhaust fans. Your ambient temp should be very high. please read this https://www.tomshardware.com/how-to/set-up-pc-case-fans-for-airflow-and-performance
 
Looking at the manual (page 22) and the following video I could potentially increase the airflow by adding more fans.

www.youtube.com

Best Full Tower of 2014 - Phanteks Enthoo Pro Case Review

Pricing:NCIX (CANADA): http://search.ncix.com/search/?qcatid=0&q=Enthoo+ProNCIX (US): http://www.ncixus.com/search/?categoryid=0&q=Enthoo+ProPhanteks is at i...
www.youtube.com www.youtube.com

Swap the front 200mm for a pair of 140mm fans
Shift my drives around - I think I can remove one 3 HDD cage if I move one SSD to one of the other mounting brackets in the case to improve air flow.
Remove the bottom cage mount and the PSU shield (far as I can tell the PSU shield is mostly just there to hide cables and make it look neat) and then put either a 140mm or if space allows 2 120mm fans
I could also put a 120mm on the side of the drive cage (as shown in the video) to help pull through air from the front fan setup.
 
A quick and easy test to do is run with you side panel off and if you see a significant improvement you know you are not getting enough fresh air in the case.

If you can get two 140mm fans in the front and remove most of the obstruction that will of course help. I'd be tempted to just remove the rear 120mm it will just be fighting the last 120mm fan on the rad for airflow.

How fast does your 200mm intake fan run? Normally they are pretty slow because of noise but a couple of companies used to make faster ones for more airflow. I don't know how many are still kicking about as 200mm fans aren't popular these days.
 
I haven’t studied your set up, but I first built my current pc with an intake front and exhaust back and top.

Much better with intake rear and front and exhaust at the top.
 
I'm assuming your CPU temps are okay but GPU is hot?

Like Overread said, that 200mm an is a piece of junk. Worst case fan I've ever seen! Replace it with a pair of 140mm and switch rear to intake and both CPU and GPU will be cooler with less fan noise. I would block all openings in front fan mounting panel not covered by intake fans so air fans push toward HDD cage and on into motherboard compartment cannot leak around into area between front grill and fans.

Case area behind fans in front of HDD cage is high pressure area.
Case area between front intake vent and fans is low pressure area.
Air fans push in circles around into front and back into fans going in circles
Blocking holes in fan mounting panel forces intake air to flow on thru case and not go in circles Tape works well.


Using rear as intake may draw a little heat from PSU and other rear venting heated air. Experiment with it and see.

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Armageus said:
Even just replacing your 200mm fan with 2x140mm should provide a decent improvement

If your current fan is the Phanteks PH-F200SP it's rated at around 186 m3/h, 2x of the below will get you over 280 m3/h



My basket at OcUK:

Total: £23.99 (includes delivery: £4.00)​

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While PH-F200SP specs look like it's a decent fan actual use has shown it simply does not do it's intended job. A single 140mm fan is way better .. and 2x 140mm fans are even better. :0)
 
doyll said:
While PH-F200SP specs look like it's a decent fan actual use has shown it simply does not do it's intended job. A single 140mm fan is way better .. and 2x 140mm fans are even better. :0)
Click to expand...
May not even be that particular fan anyway, often the bundled fans in cases are cheaper models that aren't available for retail.

Either way 2x 140mm will be much better ;)
 
So having had a look at a few things here's my current thoughts:
1) The current fan controller that the case fans are connected too has 3pin connectors for the fans and a 4 pin that connects to the motherboard CPU Fan opt (as stated in the case manual). As this controller can only take 3 pin and has a max of 30W total output chances are it won't be using it for anything save the rear fan.

case manual; Fans - page 31

2) Looking at the manual for my motherboard I've got CHA_Fan1p; CHA_Fan 2,3,5 (4 is free but might be blocked by the radiator at the top). I assume CHA Fan1P is the same as the other channel fans and the p might just denote that it works with the AIOPump if if that is in use. So in theory I can add between 3 and 4 additional fans before I'd have to consider a fan hub.

motherboard manual; Page 1-2


3) Current plan:
a) Remove 140mm fan and add 2x Noiseblocker NB-eLoop B14-PS 140mm fans to the front of the case and connect to CHA FAN connectors on the MB.
b) Remove 1 HDD cage (bottom) to help improve airflow.

This then leaves me either 1 or 2 free fan slots on the MB. 2 if CHA_FAN1p functions normally.
I've then got options of adding at least one or two fans in the following spots:
a) To the remaining HDD cage so that air flow from the front is maximised - 120mmfan
b) To the bottom of the case to add more air intake; just remove the PSU shield and add a 140mm fan.
c) Change the rear fan from a 3pin controlled via the case controller to a 4pin fan; 140mm fan
 
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