Let's talking cooling

Specifically airflow, and which directions work best.

This is my case. There are many like it but this one is mine.


I'm at work so I don't have pictures of my actual PC but I'll try to lay out the general outline.

I've got the 120mm fan on the front pulling into the case.
2 120mm fans on the top pushing out.
120mm on the rear pushing out.
120mm on the side (top port level with the CPU) pushing out.

I've also got the power cables routed behind the MoBo panel all nice and pretty.

Now, for whatever reason I've subscribed to the theory that pushing hot air out is a little more important than pulling cool air in, which is why I've got my airflow set up the way I do. I ran into serious CPU heat issues last night after installing my new GTX970 (which sits steady at 75C under full stress load BTW) and have probably had them for longer without realizing it. I have already ordered a CPU liquid cooler but since I'm going to have everything apart anyway I want to make sure my airflow is optimized without having to swap fans and test readings around 14 times.

My general thought is cool air in from the front, hot air out through the top and back. My plan is to set up the radiator on the rear panel to push out and swap the side fan around to pull in, thus creating a steady air stream for the CPU radiator as well as reinforcing the air flow from the front to push some more over the memory and MoBo heat sinks. I can also remount the existing rear fan onto the side panel, thus having 3 120mm pulling in (1 front, 2 side) and 3 120mm (1 rear, 2 top) pushing out.

People who have done this far longer than I have, does this sound reasonable? Would it be better to have the side fans pushing out rather than pulling in? Or maybe even top side fan in and bottom side fan out to assist the fans on the bottom of the GPU?

 

Obviously it is important to push hot air outside from the case. If you're sucking in more than your fans are pushing out, it will seep from whatever holes there are.

The whole point of heating is of course to get maximum airflow passing through the heatsink. Through it. The other factor is the temperature of the air passing the heatsink. For example CPU liquid cooler is nice because it usually attaches to top or some wall so once the air is heated in by the heatsink it is already exiting the case. But it's pulling air from inside the case.

The thing about pushing hot air from the case as efficiently as possible means that new air will replace that air from all possible paths it can enter. You don't need to work hard to pull more air in. If you do the opposite, the hot air will circulate within the case and will have more interaction with surfaces before exiting through various holes and cracks.

Graphics cards without liquid cooling also pull air from inside the case and there should be a nice airflow past the ram and parts of motherboard can pick up heat as well as well as HDD drives.

Try to push out more air than you're pulling in so the cooler air gets sucked in from the cracks and such rather than hot air being pushed out through them.

Just, keep in mind that you want to be pushing as much cool air as possible through each heatsink and have some general air circulation in the case to make sure the passively cooling parts stay cooled as well. It's ok to create a vortex of sorts inside the case but try to push out more.

 

I definitely want at least as much going out as I do coming in. My idea for the 3 in 3 out was mainly for constant flow velocity but what you're saying about intake coming from anywhere makes sense.

I think I'm going to try the last option in my OP - front fan in, top fans out, rear fan out, upper side in (to create more flow over the MoBo sinks) and lower side out (to help vent hot air from the GPU fans). That way at least the GPU heat isn't recirculating back up over the MoBo on its way out through the exhaust fans.

 

Be mindful of your CPU fan.

 

CPU fan is going away, replaced with a liquid cooler. Radiator for the cooler is going to be on the rear panel with the fan pushing air out through it.

 

I would not configure it that way, personally.

You want to create a flow of air. Also, keep in mind that your graphics cards are pulling air from inside the case and dumping it out the back (if it is a 2 slot card, which I assume it is). So you want to get cool air over those cards, which is what those side fans are meant to do. I would not personally have 2 fans on the side, if you DO want to have a fan on the side, put on pulling air in. Then have your 2 exhaust and 1 exhaust on the back. I think pulling air away from your GPU is actually going to do more harm then good. Let cool air be pushed to it, and let the general flow the case move other heat.

IF you were going to do 2 fans on the side, I would switch them, like I said, to pull cool air over the GPU.

I do not have the same case. But mine is set up with 2 intake fans on the front, 2 exhast fans on the back, and one large exhast fan on the top. There is also an intake on the side which pulls some air over the GPUs. I have not had much trouble with cooling, except when my filters get clogged on the front intake fans.

 

Hmmm double post, with that avatar... I think I missed that somewhere, my bad.

 

I had the GPU fans backwards then, for some reason I thought they pulled in from the rear and dumped heat down. That definitely changes things. I'll start with the 2 side and 1 front in with the 2 top and 1 rear out and see what that gets me.

 

That is how my cards work, the new ones may be different...

 

my case has twin 80s in the front sucking in cold air with twin 80s on top, 120 rear and 80mm power supply fan blowing exhaust. my cpu heatsink has a pair of 120mms moving air from front to back in line with the flow. 200mm door fan is blowing into the case as the main source for the video cards fresh air. Seems to all work, rig runs about 20-22c under full load like SC or DA:Inq. I always figured cooling was a "side" game. If your pulling in from two sides, exhust from two other sides. just remember a PC has 5 sides you can easily use to cool. I guess you could mount it on a grate with refrigerated air blowing up from the bottom to use all 6 sides.

 

I guess I really need to watch it with the side panel off and confirm if the GPU fans are pull or push. If the EVGA ACX video is to be believed they pull from the case but I can't seem to find any literature which gives fan flow direction for sure.

So if I'm reading that correctly the blades angle clockwise so the fan rotates counter-clockwise, meaning it does pull air from inside the case and pushes across the heat sink and out the back.

EDIT: Actually since this isn't a closed design most air won't actually go out the back, it'll probably float back through the case. Hmm.

Yay I'm learning things! Thanks for all the responses.

 

you could always use smoke (like a fog machine) and watch the flow of air though the case. I've done it more then once to see how well a case worked.

 

I do plan on getting another case eventually but it might be late this year or next year. Wife and I are looking at buying a house soon and when we do I'll have a bigger office in which to put a bigger desk that will fit a full tower.

 

gihzmo is right.

Make sure the front -> back & top flow is strong and then the side fan will pull in without interfering the airflow.

The whole shape of modern two-slot GPU's is such that they 'always'* pull from the case. When it's running hot, place your hand at the little exhaust holes at the back of the case.

*except if when they don't
http://www.gigabyte.us/MicroSite/275/home.html






(to hell with it if I can't post a pic of mine every time we talk about computers..)

I personally have Corsair 500r with
Intake:
lower front 2x 120mm
lower side 1x 200mm

Exhaust:
lower back 1x GPU (3x, 1 Power (80mm), 1x 120mm
rear top 1x h110i (2x 140mm)

In total there's more air being pushed outside and in general the air moves from lower front towards upper rear and lower rear. There's nothing at front top (no optic drive, I have one but haven't needed it) so I can have the air flow right past the GPU and motherboard with the 200mm feeding extra cool air straight for the GPU. The airflow from lower front to rear top also nicely goes right past the ram blocks.

 

Also, if you want powerful fans don't forget about Noctua's industrial grade series. They're about 4x as good at moving air as ordinary ones. They even have extra models that are for difficult conditions and can sustain water and dust, just in case you need something for such environments or if you're into pouring liquids and throwing sand on your computer - so you'd know at least the fans will survive.

 

Grrrrrr.......

I got my cooler in but had to remove a top fan to get it to fit. Still seems to be doing well for now, will need more stress testing later. So far hottest CPU core has been 47C during benchmarking.

I also tuned my GPU fans a bit, now under full benchmark load heat never got above 65C.

 

I have a CM HAF 932 case. have two 230mm fans, one the front and one on side, and one 120mm fan on the bottom all sucking air in. Then the 140mm on the back and then three 120mm fans on the top pulling air out. The CPU fan blows towards the rear through a standard multi veined air cooler.

 

My PC runs with two 120mm fans pulling in air from the front, while two 120mm fans push it out the top, and one 120mm pushes it out the back. Haven't had any heat issues. I still use the stock CPU fan for my i5, and of course have the three fans on the 970 that were shown in the pictures posted.

I actually had installed the fans backwards, so the two in the front were pulling out air as well, at first. Swapped them around a few days ago, and now they're pulling air into the case.

I was having an issue with my power supply overheating, but that's because I had it turned upside down, so the fan was over a vent (and filter) at the bottom of my case. Problem is, my case sits on carpet.... Yeah.. Bonehead mistake. Turned the power supply right-side up and haven't had anymore problems.

 

Gonna hijack this thread instead of creating a whole new one.

Took apart my pc and dusted everything, then reassembled and booted up. Now my cpu overheats with 40-50% loads, I can't open more than 3 tabs in firefox and if I even think of opening a game it screams for mercy. I have the Corsair H80 and both radiator fans are working normally so I'm wondering if the pump has died. Anyone have thoughts on this?