Question Need help choosing proper cooling for my build ?

[mazinyo]

The case is the 4000D Airflow and the GPU is 3880 FTW, which will probably generate more heat.

It gets pretty hot here in the summer where I live so I need proper cooling but not something too expensive. Just something good that will do a good job. No interest in water cooling.

1. CPU -I7 12700F - I am trying to decide between the be quiet! CPU Cooling Dark Rock 4 and the Noctua NH-D15. The D15 is a little more expensive

2. Case fans - Was thinking about TWO Noctua NF-A14 PWM 1500 RPM 140MM Premium Fan in the front and ONE Noctua NF-A12x15 PWM 120MM Fan in the back. Or Silent Wings 3 with same setup. Any thoughts? suggestions?

3. The case comes with 2 120mm fans. Should I do something with them? On top maybe? Or is it too much and will just add more dust to the case?

Any thoughts or suggestions would be really appreciated

 

[Phaaze88]

1)Are Deepcool's AK620, Scythe's FUMA 2, Thermalright's Frost Commander 140 or Peerless Assassin, available to you? They should be more affordable than either of those.

2)Just a suggestion, but I wouldn't bother with a 120mm rear fan right behind 140mm ones, except for looks. In practice, it's more likely to not really make a difference if it were there or not. I don't know why Corsair restricted the rear fan slot to 120mm...

3)You can put them up top as exhaust to help get the gpu's heat out faster, or store them somewhere to use as spares.

 

[mazinyo]

1)Are Deepcool's AK620, Scythe's FUMA 2, Thermalright's Frost Commander 140 or Peerless Assassin, available to you? They should be more affordable than either of those.

2)Just a suggestion, but I wouldn't bother with a 120mm rear fan right behind 140mm ones, except for looks. In practice, it's more likely to not really make a difference if it were there or not. I don't know why Corsair restricted the rear fan slot to 120mm...

3)You can put them up top as exhaust to help get the gpu's heat out faster, or store them somewhere to use as spares.

1. None of the models you mentioned are available where I live. There is also the option of Noctua NH-U12S
2. Ok fair enough. So should I just put 2 x 140mm or 3X120 mm in the front and nothing in the back?

 

[Phaaze88]

1)Well, that's a bummer...
No, on the NH-U12S.
Between the Dark Rock 4 and NH-D15, I'm going to lean towards the NH-D15... unless you meant the Dark Rock PRO version? If that were the case, I guess it'd be a toss up between looks.

2)If you want. Again, it was just a suggestion.

 

[mazinyo]

1)Well, that's a bummer...
No, on the NH-U12S.
Between the Dark Rock 4 and NH-D15, I'm going to lean towards the NH-D15... unless you meant the Dark Rock PRO version? If that were the case, I guess it'd be a toss up between looks.

2)If you want. Again, it was just a suggestion.

1. No, I meant the DR 4, not the PRO. The DR PRO is about $10 cheaper than the D15 here

2. I dont know what is more effective, thats why I am asking. Are 2X140mm NF A14 be enough in the front?

 

[Phaaze88]

1)DRP4 = NH-D15 > DR4.

2)Yes.
I would opt for 140mm fans over 120mm ones every time. Generally move more air than 120mm at lower rpms, while being just as inaudible.
1500rpm or higher? Well, practically any chassis fan is going to be audible by that point, or before it.

 

[mazinyo]

I have watched some youtube videos if the D15 inside the 4000D AF and it looks quite crowded in there together with a mighty 3080 . The D15 is quite big,

 

[Lafong]

If you tried the U12S or U14S, your temps would be higher than the D15, but not a lot higher....I wouldn't have any qualms about either unless you are temp obsessed. Maybe you are. I have no idea.

 

[KyaraM]

1. No, I meant the DR 4, not the PRO. The DR PRO is about $10 cheaper than the D15 here

2. I dont know what is more effective, thats why I am asking. Are 2X140mm NF A14 be enough in the front?

If the Dark Rock Pro 4 is cheaper than the Noctua, go with that. The difference is minimal, and the Noctua is, quite frankly, both ugly as hell and far too big for many cases. The Dark Rock Pro 4 is both smaller and has similar performance, so for 10 bucks less it's honestly a no-brainer.

About the fans, I use one 120mm in the back and 1 140mm above the CPU, for exhaust, 2 140mm in the front and 1 120mm on top in front of the CPU for intake. All from BeQuiet!. But two 140mm front should be sufficient intake, depending on the case. The top intake, in my case, does lower CPU temps by about 5°C, but that doesn't mean it has to be same for you. It depends on your case. In most cases, it should be sufficient.

 

[Karadjgne]

1. Those big double towers are effectively the same thing. A DRP4 = D15/S = Assassin 3 etc. It's mainly looks that seperate them at that level of ability.

2. Fan types are important. The Noctua Ax25 series are solid performers, but very in the middle. They have decent CFM capability, but also decent SP which makes them great for higher pressure needs of intakes or heatsinks/rads, but not so good for exhausts. There's no need for pressure at exhaust, it's all about moving air and the Silent Wings AF do it better.

3. Rear exhausts are a dinosaur. Years ago, AT cases were solid top, no venting. All you had was a rear exhaust fan, that was it. It wasn't until more recently that case top venting and case thermals were considered important. Hot air from a gpu goes basically straight upwards, most stock downdraft heat goes up, so top mounted fans are a plus. Rear just confuses things, trying to bend natural convection 90°. Unless you use a tower-rear facing cooler, since that airflow Is directed at the rear.

It's one of those situations where you'll need to experiment. 1 fan at top-rear, 2 fans at top, rear exhaust or not. Most pictures you'll see online are showcase builds, designed for looks over performance. Fill all the fan slots if you want that look, but less fans can and usually does perform better than more fans. Where those fans go will be determined by the case, intakes etc.

 

[Phaaze88]

I suggested no rear exhaust fan being due to having tested it with my hardware(up to date link in sig), but it's a dual AIO system, and the CM H500P Mesh supports rear 140mm fans.
Didn't make a noticeable difference whether it(NF-A14) was intake, exhaust, or not there at all, so I left it out... wouldn't be surprised if top mounted AIOs didn't really need a rear fan either, but fewer and fewer people seem to do their own testing anymore, and sometimes underprovision with some 240mm AIO, /LE SIGH

120mm air towers are more likely to see some benefit from a 140mm rear exhaust.

 

[mazinyo]

How about 2X140mm Noctua in front, 1X120mm stock fan rear and 1X120mm stock fan top rear above the CPU?

 

[scout_03]

these are the case oem fns no specs https://www.corsair.com/us/en/Categ...120mm-3-pin-Fan,-Black,-1200-RPM/p/CC-8900456 and look at hese double kit for the 140 mm at 62 cfm 2 in front one top one back .

 

[Phaaze88]

How about 2X140mm Noctua in front, 1X120mm stock fan rear and 1X120mm stock fan top rear above the CPU?

The staple 4 fan configuration. 👌
Test and find out - see if it makes any real difference.

 

[Karadjgne]

wouldn't be surprised if top mounted AIOs didn't really need a rear fan either,

I ran a 280mm AIO as exhaust and 2x 140mm intakes for years. Rear exhaust only added noise and added 2°C to cpu temps as it was stealing air from the nearest AIO fan. In a supposedly bad airflow Fractal Design R5 with the door closed.

Changing fans for AIO did nothing but drop cpu 2° and add 2° to the gpu as it saw lowered airflow after diffusion from the rad. Had to move the rad fans to pull to get that 2°C gpu temp back. Exhaust fan didn't change temps, just added noise.

How about 2X140mm Noctua in front, 1X120mm stock fan rear and 1X120mm stock fan top rear above the CPU?

Best setup for most case airflow patterns with a tower cooler. The Noctua have enough static pressure and cfm to make sure the gpu gets plenty of air.

 

[Phaaze88]

Rear exhaust only added noise and...

See, that's what I observed with a top mounted AIO, and even back when I was using the D15S; it made more noise than it contributed to cooling the hardware, so I disregarded it.
I don't look inside the PC except during troubleshooting or maintenance anyway, so that 'empty space' doesn't bother me.

 

[mazinyo]

I ran a 280mm AIO as exhaust and 2x 140mm intakes for years. Rear exhaust only added noise and added 2°C to cpu temps as it was stealing air from the nearest AIO fan. In a supposedly bad airflow Fractal Design R5 with the door closed.

Changing fans for AIO did nothing but drop cpu 2° and add 2° to the gpu as it saw lowered airflow after diffusion from the rad. Had to move the rad fans to pull to get that 2°C gpu temp back. Exhaust fan didn't change temps, just added noise.

Best setup for most case airflow patterns with a tower cooler. The Noctua have enough static pressure and cfm to make sure the gpu gets plenty of air.

Come to think about it, the top fan will be completely obstructed by the CPU heatsink, so Im not sure a top fan will add something substantial

 

[Phaaze88]

Come to think about it, the top fan will be completely obstructed by the CPU heatsink, so Im not sure a top fan will add something substantial

Not for the cpu, at least.
Gpus that dump their waste heat inside the PC are what benefit from those top exhausts, by helping to get it out faster.

 

[mazinyo]

Not for the cpu, at least.
Gpus that dump their waste heat inside the PC are what benefit from those top exhausts, by helping to get it out faster.

But the CPU heatsink will be in the middle anyway and block most of it

 

[Phaaze88]

But the CPU heatsink will be in the middle anyway and block most of it

Not really. The air's going to get pulled through the finstack, and around it.

 

[Karadjgne]

Because of the pitch of the blade, when it moves through air it creates a low pressure area directly behind it. When combined with other blades spinning, it creates a stronger low pressure area that spreads out in front of the fan. Faster the blades, stronger and lower that pressure gets. The byproduct is the breeze you feel from the back of the fan.

Nature abhors a vacuum, so air at a higher pressure, like that in the case supplied by the intakes, will physically move to the lower pressure area, rinse and repeat in a constant flow.

So as long as there's over half an inch of space in front of the fan, it's going to act like a vacuum source and air Will move to fill it. It's not a directional vacuum force, like the fan exhaust, but an area force.

As such, the last thing you want is an exhaust directly in front of the cpu cooler. That puts a strong negative pressure area in the top front quadrant, so that's where the case air will want to go, when you need it to go to the rear. If anything, a fan on top as intake, at a static low rpm will help feed the cpu cooler, but at low rpm doesn't have sufficient static pressure to overpower the case front intakes or enough vacuum pressure above it to pull the faster moving top exhaust heat.

Once you figure out how fans work, picturing airflow patterns gets easier and you can tailor fan curves and fan types and placements to better fit the overall airflow, which helps temps. I'd rather have cpu temps that stay consistently 50-70° than one that varies from 30-90° depending on loads. But thats essentially what a full custom loop establishes vs aircooling.

 

[mazinyo]

Because of the pitch of the blade, when it moves through air it creates a low pressure area directly behind it. When combined with other blades spinning, it creates a stronger low pressure area that spreads out in front of the fan. Faster the blades, stronger and lower that pressure gets. The byproduct is the breeze you feel from the back of the fan.

Nature abhors a vacuum, so air at a higher pressure, like that in the case supplied by the intakes, will physically move to the lower pressure area, rinse and repeat in a constant flow.

So as long as there's over half an inch of space in front of the fan, it's going to act like a vacuum source and air Will move to fill it. It's not a directional vacuum force, like the fan exhaust, but an area force.

As such, the last thing you want is an exhaust directly in front of the cpu cooler. That puts a strong negative pressure area in the top front quadrant, so that's where the case air will want to go, when you need it to go to the rear. If anything, a fan on top as intake, at a static low rpm will help feed the cpu cooler, but at low rpm doesn't have sufficient static pressure to overpower the case front intakes or enough vacuum pressure above it to pull the faster moving top exhaust heat.

Once you figure out how fans work, picturing airflow patterns gets easier and you can tailor fan curves and fan types and placements to better fit the overall airflow, which helps temps. I'd rather have cpu temps that stay consistently 50-70° than one that varies from 30-90° depending on loads. But thats essentially what a full custom loop establishes vs aircooling.

Thanks for this info. So you suggest to avoid a rear fan

 

[Karadjgne]

No. I suggest you experiment. Try the pc with a fan, without a fan, deeper and shallower curves, higher and lower speeds etc. Case airflow changes on a case by case basis, what's perfect for one setup may be a disaster for another.

There's a hundred case designs all very similar to the nzxt H500 series. All the same box with a hard cover and little vents for the front cover. But for some strange reason, that series does best without any fans in front at all. All exhaust fans at rear/top. Other cases similar need front fans and no exhaust fans.

Airflow can change just by using a different gpu, different cpu cooler, different fan types, more/less fans, bigger/smaller fans, wiring layouts or lack of, hdd trays, shrouds etc. There's only a general guide line, air in front - out back, but that is general, not specific.

It's upto you to figure out what works best for you, your case, your components, your hearing and aesthetics. Some don't care about the noise, doesn't bother them, so turn the fans to full blast and leave them there. Some prefer as silent as possible so fan speeds are minimum to move air. That affects temps both ways, but each person has to find their happy place between what noise and what temps they can live with, and what changes need to be made to achieve their goals.