Question Aio, air cooling, airflow and fan size. I’m a newbie, help!

[Dekb97]

Ok guys. My 6yr old pc got fried, so I’m building a new one. Hardware is determined, but I’m not sure about cooling. I’m building a lightning ship (full rgb), and since I care lots about looks, I’m looking into aio. FYI all my other rgb hardware is Corsair. So:

Corsair h150i aio with replaced fans (Corsair LL120) or a good air cooler (Darck Rock Pro4)? Pros and cons?
I want good perfomance and looks.

Also: my case is p400a with mesh front so there won’t be too much flow restriction on the intake.

Either way (air or aio), do I put an 140 or 120 on top as exhaust? The non-used top fan slot will be mounted with an dust filter in addition to the filter allready sitting on the outside of the case.
Anyhow I’ll have an 120 in the back. I want a slight positive pressure since this seems the way to go.

Ty all and sorry for bad english.

 

[Karadjgne]

Wondering why you'd pull off the much better ML series fans off the H150i, both are rgb. Performance will also take a nose dive if replacing the 135mm fans on the DRP 4.
The LL120/140 really aren't suited for either application for optimal cooling. You'd be far cheaper to use a Evga CLC360 or a fractal design S36 and replace those fans with the LL's.

Pressure is totally misunderstood. Anywhere there's an exhaust fan, there's a low pressure area that's in front of it. It's going to pull air from the surrounding space, that includes pci slits, unused portions of fan grills, gaps, anywhere where the pressure is slightly higher and easily available. At idle speeds you'll almost always have a negative system as pull/draw from the exhausts is stronger than the intake pressure. Regardless of fan sizes. You'd have to have overwhelming fan differences, like 3x higher rpm balanced fans vrs a single exhaust in a case that's leak sealed to get a positive pressure in the case. It's only when rpms are closer to max that cfm/sp from intakes has a chance to exceed the draw from the exhausts. And become positive.

The only thing that really matters is air Flow. And that's different in an aio based pc than from air cooler based. Placement of the rad can also change characteristics. With front mount aio, better to have 2x top mount exhausts and seal the rear exhaust grill. With top mount aio, better to have low mounted intakes (low front/bottom) and seal the top-front and rear exhaust. Chimney affect, creates/helps natural tendencies for warmer air to rise unidirectional. Up and out.

With air cooling, gotta have the rear exhaust, the tower is shoving warmed air in that direction, better to suck it straight out. Don't use top-front for exhaust, that creates cyclical airflow, not smooth transitions. Don't use top-front for intake as that feeds the cpu cooler (which is nice) but pushes heated air back into the case below the cooler, which is then picked up by the gpu. Cyclic again.

A good, uniform, flow is far more important, and helpful overall, than worrying about positive/negative pressure.

 

[Dekb97]

Wondering why you'd pull off the much better ML series fans off the H150i, both are rgb. Performance will also take a nose dive if replacing the 135mm fans on the DRP 4.
The LL120/140 really aren't suited for either application for optimal cooling. You'd be far cheaper to use a Evga CLC360 or a fractal design S36 and replace those fans with the LL's.

Pressure is totally misunderstood. Anywhere there's an exhaust fan, there's a low pressure area that's in front of it. It's going to pull air from the surrounding space, that includes pci slits, unused portions of fan grills, gaps, anywhere where the pressure is slightly higher and easily available. At idle speeds you'll almost always have a negative system as pull/draw from the exhausts is stronger than the intake pressure. Regardless of fan sizes. You'd have to have overwhelming fan differences, like 3x higher rpm balanced fans vrs a single exhaust in a case that's leak sealed to get a positive pressure in the case. It's only when rpms are closer to max that cfm/sp from intakes has a chance to exceed the draw from the exhausts. And become positive.

The only thing that really matters is air Flow. And that's different in an aio based pc than from air cooler based. Placement of the rad can also change characteristics. With front mount aio, better to have 2x top mount exhausts and seal the rear exhaust grill. With top mount aio, better to have low mounted intakes (low front/bottom) and seal the top-front and rear exhaust. Chimney affect, creates/helps natural tendencies for warmer air to rise unidirectional. Up and out.

With air cooling, gotta have the rear exhaust, the tower is shoving warmed air in that direction, better to suck it straight out. Don't use top-front for exhaust, that creates cyclical airflow, not smooth transitions. Don't use top-front for intake as that feeds the cpu cooler (which is nice) but pushes heated air back into the case below the cooler, which is then picked up by the gpu. Cyclic again.

A good, uniform, flow is far more important, and helpful overall, than worrying about positive/negative pressure.

That’s really technical, thanks mate. Wanted to replace the ML cause I think they’re ugly tbf.. And the LL is really good looking imo. All things in consideration, what would you suggest me to do?

 

[Karadjgne]

Because of height limitations, Phanteks has stated no rads on top, basically its room enough for fans only. That leaves the front. Which can handle 280mm or 360mm AIO's. I ran a 280mm in front with 2x 140mm up top for years, never an airflow issue or case temp issue in a closed front Fractal R5. On a 4.9GHz i7-3770K @ 200w.

So the question really is, is what fans and where. And that's going to be on your tastes. The 280mm/360mm won't make much (if any) difference to any cpu other than the i9 9900k/s, so anything lesser can easily be cooled by either size. So do you want 3x 120mm fans or 2x 140mm fans in front. Both going to perform about the same.

2x 140mm on top, either cover the slot or use a fan at rear, up to your tastes and wants, it's not needed.

 

[Dekb97]

Because of height limitations, Phanteks has stated no rads on top, basically its room enough for fans only. That leaves the front. Which can handle 280mm or 360mm AIO's. I ran a 280mm in front with 2x 140mm up top for years, never an airflow issue or case temp issue in a closed front Fractal R5. On a 4.9GHz i7-3770K @ 200w.

So the question really is, is what fans and where. And that's going to be on your tastes. The 280mm/360mm won't make much (if any) difference to any cpu other than the i9 9900k/s, so anything lesser can easily be cooled by either size. So do you want 3x 120mm fans or 2x 140mm fans in front. Both going to perform about the same.

2x 140mm on top, either cover the slot or use a fan at rear, up to your tastes and wants, it's not needed.

Thank you buddy! Actually, the phanteks p400a supports a 240 rad in the top.

Anyways, what I could do then if I understood you correctly is to place a 360 rad in the front, and then 2x140 as exhaust in the top.

If I do put a 120 in the back, do I connect it? Or use it as a seal? Didnt quiet get that part.
Again thanks lots

 

[Karadjgne]

Yes, 2x 120mm fan holes does equal a 240mm rad in most cases, however, that's vertical size, not horizontal size. What you'll find is that many times the depth of the rad + depth of the fans shoves the whole thing into the motherboard, and you'll end up with ram clearance issues, header issues even heatsink issues. If you look at Phanteks website, about halfway down you'll see 2x pictures. The first is for Fan support and includes a listing of lines for top fans.
The second is Radiator support and the top lines are missing, only shows support for for front/rear.

 

[Dekb97]

Aha, yes I see. Thx for clarifying mate. Not sure what I'll do..

 

[Dekb97]

Yes, 2x 120mm fan holes does equal a 240mm rad in most cases, however, that's vertical size, not horizontal size. What you'll find is that many times the depth of the rad + depth of the fans shoves the whole thing into the motherboard, and you'll end up with ram clearance issues, header issues even heatsink issues. If you look at Phanteks website, about halfway down you'll see 2x pictures. The first is for Fan support and includes a listing of lines for top fans.
The second is Radiator support and the top lines are missing, only shows support for for front/rear.

At this point I'm down to the following options: (please tell me what you would suggest me to do. I'm very sorry if you allready did, I'm just not that great at understanding english).

a) A 240 rad as intake in the front. 2x140's as exhaust in the top. Sealed back.

b) A 240 rad as intake in the front. 2x140's as exhaust in the top, 1x120 as exhaust in the back.

c) A 240 rad as intake in the front + 1x120 in the front as intake. 2x140's as exhaust in the top. Sealed back.

d) A 240 rad as intake in the front + 1x120 in the front as intake. 2x140's as exhaust in the top, 1x120 as exhaust in the back.

e) A 360 rad as intake in the front. 2x140's as exhaust in the top. Sealed back.

f) A 360 rad as intake in the front. 2x140's as exhaust in the top, 1x120 exhaust in the back.

Also, would it be THAT bad to replace the ML's on the rad with the LL's?

I appriciate your help greatly man, really do. Thank you lots.

 

[Karadjgne]

a) works
b) same as a)
c) can work, but only in Push and the reservoir will slightly cover part of the 1 fan (top or bottom) not attached to the rad.
d) same as c)
e) works
f) same as e)

It's really upto you, what you plan and the fans used. A 240mm AIO is fine. A 360mm AIO will mostly work the same as a 240mm but has higher capacity and is better for the biggest power hog cpus. It also costs more. And then there's the RGB, some ppl want as much as possible, so flood the case with fans, just to get it.

As long as air comes in the front/low and out the top/rear it's a personal decision as to looks.

The ML's are built for a rad. Their design is meant more for static pressure to force air through the fins, the LL's do better as case fans. They'll work on a rad, just not as well as the ML's. Sometimes performance is sacrificed for looks, sometimes looks are sacrificed for performance. Kinda up to you which way you go.

I personally would use the ML's in Push, bury them behind the rad, I'd use a 360 for the performance and looks, keeping rpm very low and quiet. 2x 140mm on top. But thats me, and I'm not a huge fan of overblown RGB, just a accent hint is good. That may not be you.

 

[Dekb97]

a) works
b) same as a)
c) can work, but only in Push and the reservoir will slightly cover part of the 1 fan (top or bottom) not attached to the rad.
d) same as c)
e) works
f) same as e)

It's really upto you, what you plan and the fans used. A 240mm AIO is fine. A 360mm AIO will mostly work the same as a 240mm but has higher capacity and is better for the biggest power hog cpus. It also costs more. And then there's the RGB, some ppl want as much as possible, so flood the case with fans, just to get it.

As long as air comes in the front/low and out the top/rear it's a personal decision as to looks.

The ML's are built for a rad. Their design is meant more for static pressure to force air through the fins, the LL's do better as case fans. They'll work on a rad, just not as well as the ML's. Sometimes performance is sacrificed for looks, sometimes looks are sacrificed for performance. Kinda up to you which way you go.

I personally would use the ML's in Push, bury them behind the rad, I'd use a 360 for the performance and looks, keeping rpm very low and quiet. 2x 140mm on top. But thats me, and I'm not a huge fan of overblown RGB, just a accent hint is good. That may not be you.

Thank you for really cutting it out for me, sir. I'll do as you've suggested: getting the 360 (mainly for looks), and then putting 2x140's in the top as exhaust. I'll keep the ML's on the rad. Now, I want to seal the rear. How do I actually seal it? Just by mounting a dust filter on the inside of the case?

And oh yes! Do I remove the dust filter from the top? It's situated on the outside of the case.

And fyi, my cpu is ryzen 7 3800x.

 

[Karadjgne]

The Ryzens do run pretty cool as far as top end output goes, a little warm on the lower end, so the 360 is going to be quiet. Bonus.

As to sealing the rear, I've seen everything from ppl using cardboard to tape to a small square of black plastic perfectly cut out and using the fan screws to hold it in place. It's really a case mod, there's no perfect solution, just whatever you can imagine.

The top filter you can leave, it serves 2 purposes, one being to cover the rad/fan area and give the case cleaner looks, the other to help prevent settling dust from going into the rad/fans when the pc isn't run. Anything that lands on it will just get blown off when you start the pc.

 

[Dekb97]

The Ryzens do run pretty cool as far as top end output goes, a little warm on the lower end, so the 360 is going to be quiet. Bonus.

As to sealing the rear, I've seen everything from ppl using cardboard to tape to a small square of black plastic perfectly cut out and using the fan screws to hold it in place. It's really a case mod, there's no perfect solution, just whatever you can imagine.

The top filter you can leave, it serves 2 purposes, one being to cover the rad/fan area and give the case cleaner looks, the other to help prevent settling dust from going into the rad/fans when the pc isn't run. Anything that lands on it will just get blown off when you start the pc.

Thank you tons man! Appriciate all your help.