Radiator and Fan Placement

I would like to hear any thoughts, opinions, etc. on WHERE the radiator should be mounted in a case IF there is room on every side. Who feels that it is better to use fans as exhaust on a radiator instead of intake?

My thoughts & opinions:

I think that just about anywhere besides the top (right over your components) is an ideal place to mount a radiator. I think that fans in a push/pull config (or not) should intake cool air through the radiator instead of trying to exhaust warm air. I think that computer cases which allow radiator mounting in front or on sides AND allow fans to be mounted on top as the ONLY exhaust fans in the case are the best cases that exist. I have had much lower temperatures at idle, overclocked, etc. when mounting anywhere besides the top.

For best temps, you should use the lowest intake temperature possible... which of course would be air that has not been circulated through the case.

Here is my take...

I prefer overall airFLOW to getting a couple C better temperatures. The idea is front/sides = intake, top/rear = exhaust. This gives you a front to back bottom to top (allowing the heat to rise thing, though negligible really) airflow. If you mount a radiator on the front the clear answer there is intake. If you mount a radiator on top, it could go either way. Clearly if you use it as an intake, you botch airFLOW but get the best temps. If it is exhaust, you can mantain airFLOW while losing a couple C.

Being properly radded is part of this discussion as well. If you are woefully under radded, you will be pumping warmer air into the case versus a system that is properly radded.

95% of people do not NEED that couple C difference in the first place as there is plenty of headroom in a custom loop or AIO for moderate overclocks. So with that in mind, why botch airflow just for a couple of C?

Clearly the best temps will be had by moving the coolest air through the rad, but the question is, to what end? Why botch airFLOW when a couple of C isn't needed?

EarthDog said:

For best temps, you should use the lowest intake temperature possible... which of course would be air that has not been circulated through the case.

Here is my take...

I prefer overall airFLOW to getting a couple C better temperatures. The idea is front/sides = intake, top/rear = exhaust. This gives you a front to back bottom to top (allowing the heat to rise thing, though negligible really) airflow. If you mount a radiator on the front the clear answer there is intake. If you mount a radiator on top, it could go either way. Clearly if you use it as an intake, you botch airFLOW but get the best temps. If it is exhaust, you can mantain airFLOW while losing a couple C.

Being properly radded is part of this discussion as well. If you are woefully under radded, you will be pumping warmer air into the case versus a system that is properly radded.

95% of people do not NEED that couple C difference in the first place as there is plenty of headroom in a custom loop or AIO for moderate overclocks. So with that in mind, why botch airflow just for a couple of C?

Clearly the best temps will be had by moving the coolest air through the rad, but the question is, to what end? Why botch airFLOW when a couple of C isn't needed?

Click to expand...

Thanks, this is the kind of feedback I wanted on this post. You have a very intelligent outlook on cooling. Everybody seems to think a little different when it comes to airflow and rad placement. I would just like to hear everybody's thoughts and opinions on it. My idea of airflow has more to do with positive air pressure. I normally use all sides except the top as intakes rads/fans and then use the top for exhaust since heat naturally rises. Using the top like a vacuum to suck out the heat.

As far as properly radding, I am planning 4 large rads or maybe 6, 4 reservoirs, and 4 pumps (for redundancy) on 2 loops. Obviously I care about those couple or few C! The end goal is just the best 24/7 CPU & GPU overclocks at the lowest possible temps.

Don't let 'pressure' be a part of the decision. Remember, you don't have a sealed case so pressure changes are negligible at best. That said, having more intake than exhaust will prevent dust from coming in the cracks of the case....... but that is about all and in order for that to be worth it, all intake locations need to be filtered.

What does "4/6 large rads" mean? Meaning what size in mm? 4/6 3x120mm (so it will fit 3 120mm fans) or...........?
What are you trying to cool as 4 rads of most any size is massive overkill on all but the most high output (think overclocked AMD octo core with 3/4 video cards). Remember, the blocks used can only put out so much heat so too much rad is just ends up costing you money in the end and that is about it there.

As far as reservoirs, you just need one for each pump. I don't see the point of so many pumps at all. But then again, you didn't mention what exactly this would be cooling. Typically, a CPU and 2 GPU loop is fine with one solid pump (I understand two for redundancy, but 4 pumps? Whaaa?!!! LOL). Why 2 loops? Again most of the time that isn't needed.

So, if you tell us what you want to cool, we can help you pick out something appropriate for your goals.

I wouldn't go as far as calling it botched air flow (lol) but more turbulent might make sense. I used to be on both sides of the fence and have experimented with both. The final verdict is all rad intakes and rear as exhaust. Best temps I could push for and even the internal case air temps doesn't get awfully warm. I am usually in the 25c-35c (idle-extreme load/Folding). I let positive pressure take control and all is said and done. Most cases are starting to come with top filters, let alone bottom and fronts so you pretty much have no choice. Yes, you have a calmer air flow by front and bottom as intakes while top and rear are exhausts. The whole heat rises imho, should really only matter if there really is no air flow because once the fans start up and a particular airflow pathway, if you will is created, that heat will follow that path and not fight with it to rise to the top, no? Correct me if I am wrong.

But yeah, I have a complete overkill system (even though I really wanted to future proof to a point that if I threw 2-3 more GPU's in the mix that I wouldn't have an issue and OCing) just because I caught the water cooling bug. I still tinker here and there. Its a fun and a expensive hobby.

Botched may be pretty strong, but it does......hmm...complicate (better? LOL!) airflow.

EarthDog said:

Botched may be pretty strong, but it does......hmm...complicate (better? LOL!) airflow.

Click to expand...

Yes, much better! I actually like that better than what I said.

EarthDog said:

Don't let 'pressure' be a part of the decision. Remember, you don't have a sealed case so pressure changes are negligible at best. That said, having more intake than exhaust will prevent dust from coming in the cracks of the case....... but that is about all and in order for that to be worth it, all intake locations need to be filtered.

What does "4/6 large rads" mean? Meaning what size in mm? 4/6 3x120mm (so it will fit 3 120mm fans) or...........?
What are you trying to cool as 4 rads of most any size is massive overkill on all but the most high output (think overclocked AMD octo core with 3/4 video cards). Remember, the blocks used can only put out so much heat so too much rad is just ends up costing you money in the end and that is about it there.

As far as reservoirs, you just need one for each pump. I don't see the point of so many pumps at all. But then again, you didn't mention what exactly this would be cooling. Typically, a CPU and 2 GPU loop is fine with one solid pump (I understand two for redundancy, but 4 pumps? Whaaa?!!! LOL). Why 2 loops? Again most of the time that isn't needed.

So, if you tell us what you want to cool, we can help you pick out something appropriate for your goals.

Click to expand...

(4 to 6) 540mm rads = overkill, 4 reservoirs = overkill, 4 pumps = overkill, 2 loops = overkill...I like overkill! The pumps are the dual Swiftech which I will get heatsinks and fans for. If a pump fails on either loop, I have a backup. I have 2 Thermaltake Core X9 cases stacked so I have to fill them with something. The cases are not really air cooling friendly, they are more geared towards building crazy liquid cooling systems. The point is that there is no point! Because I can! I have seen the Lian Li desk cases with 2 loops, 4 reservoirs, etc.

Interesting viewpoints also. All I really meant by positive air pressure is more intake fans than exhaust fans. I have so many intake fans right now that I never see above 35c on CPU or 45c on GPU. That's with CM Nepton 280L in push/pull with Noctua Industrial IP67 140mm 2000RPM PWM fans. I guess I have outgrown air cooling and AIO coolers. I always said that if I ever do a liquid cooling system that I would go crazy extreme.

I think that trying to fight the laws of physics botches the lowest possible temperatures. It's like saying yes heat rises but it doesn't really matter. Can it make a difference? I guess it depends on your system maybe but it has made a difference for me in all my builds since 1995. Sometimes it's only 2 to 3c, other times more. My cases are basically forcing me to use the top for rads so I guess I'm just trying to hear as many educated opinions as possible so I can figure out how I want to direct my airflow. If I have to exhaust air through rads mounted on the top then I will want a ton of intakes.

You want Overkill you ask?!!!! FINE! Feast your eyes on this!!!

But in all seriousness, if you want overkill fine but what you're saying is a wee bit beyond overkill to another "territory", if ya catch my drift. Trust me, I am an overkill kind of guy.

You got tons of cash to blow? Grab a 900D case ($300+) or a Caselabs ($1000+). Throw w/e you want at it than after that. Buy eLoop B12 PWM fans with a Aquaero 6 for full monitoring and control. Better yet, buy the pumps in serial, tube reservoir w/ LED + water level sensor, flow meter, many more sensors (lol), etc all from Aqua so its all compatible with their Aquaero 6. That there should run you close to $1000. Than grab monsta (80mm) rads, depending on the case, fill it up except the back as exhaust. Make sure you go push and pull because those rads are very thick. With that much of a cooling system you can throw anything at it. Go with Bitspower compression fittings and primochill advanced LRT tubing.


There, that's a overkill rig. Not what you posted. lol

GTXJackBauer said:

You want Overkill you ask?!!!! FINE! Feast your eyes on this!!!

But in all seriousness, if you want overkill fine but what you're saying is a wee bit beyond overkill to another "territory", if ya catch my drift. Trust me, I am an overkill kind of guy.

You got tons of cash to blow? Grab a 900D case ($300+) or a Caselabs ($1000+). Throw w/e you want at it than after that. Buy eLoop B12 PWM fans with a Aquaero 6 for full monitoring and control. Better yet, buy the pumps, flow meter, sensors, etc all from Aqua so its all compatible with their Aquaero 6. That there should run you close to $1000. Than grab monsta (80mm) rads. Make sure you go push and pull because those rads are very thick.


There, that's a overkill rig. Not what you posted. lol

Click to expand...

Love that desk! I am an extremist...so if by another "territory", you mean insanity...well yeah I'm probably crazy...but in a good way. I may use Aquacomputer reservoirs actually. Alphacool NexXxoS UT60 Full Copper 480mm or 560mm...Monstas are too thick. I have been eyeballing Caselabs for years, waiting for them to do a horizontal motherboard tray with side mounted rads case. Case manufacturers and designers seem to force feed us cases where we can only mount large rads on top...I am breaking out of that nonsense! I am trying to be respectful of everyone's thoughts and opinions...so please...no need for sarcasm.

Merged triple posts...

So.... Again, what hardware are you planning to cool?

Planning for the future...so Skylake-E & GTX 1080's...or whatever they will call them...I know that it is beyond overkill...I may end up just doing 2 MCP655's but I am definitely doing separate loops for CPU & GPU's with thermal sensors, flow meters, whole nine yards. Every stacked Core X9 at CES 2015 had separate loops.


Oh and the Core X9 is sold out everywhere so no triple stack...for now!

Shannon! I missed CES this year with our editing staff... Next year again though!

When are you planning on building this since the parts you listed won't come out until 2016+?

Anyhoo, I'm too much about fiscal responsibility, so I will back out gracefully and keep an eye out for a build log. Cant wait! I am going to build in that same case here soon.

I will await for this build log as well. GL OP on your adventure.

EarthDog said:

Shannon! I missed CES this year with our editing staff... Next year again though!

When are you planning on building this since the parts you listed won't come out until 2016+?

Anyhoo, I'm too much about fiscal responsibility, so I will back out gracefully and keep an eye out for a build log.

Click to expand...

I am going to do Skylake mainstream first until Skylake-E hits...this will allow me to get other stuff going like the Samsung SM951 or possibly a SATA Express drive...I just want NVMe! I also want the Acer XB270HU...I will post pictures when everything is completed.

Thank you kind sirs...and I do understand why it is overkill/not needed...it will be fun though and I will make it all look good!