[SOLVED] New Rig, Radiator as Bottom Intake

GodsArmada

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Apr 14, 2013
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So my new rig contains:
I7 9700K
EVGA 2060 XC Ultra Gaming
MSI MPG Z390 (mobo)
3 Coolermaster Air Fans
1 360mm CPU cooler AiO
Case is a Rosewill Prism S Lite. It has intakes on the bottom of the case and the PSU and Hard drive bay on top of the case.

What I was concerned about, which was brought up by others, is that the Radiator for the CPU cooler being used as an intake on the bottom of the fan will just cause hot air to be blown into the rest of the case. Now it is obvious that if the radiator was blowing out it would not be blowing "hot" air into the case. However my initial train of thought was that if I put the CPU cooler on the bottom of the case then it would be able to pull the coldest air into itself, therefore making it more efficient for the CPU.

Will this actually cause an issue with the rest of the computer where it will cause it to heat up, especially the GPU since it is blowing straight into it?
 
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I7 3770k @ 4.9GHz OC. Gtx970 OC 124%. Kraken x62 silent mode. Prime 95 small fft/msi kombuster. Mounted pull/intake Cpu 70°, gpu 82°. Mounted as push/top exhaust Cpu 72°, gpu 80°

4x 140mm fans total in Fractal Design R5 Window (not an impressive airflow case), front door closed. 2x intake, 2x top exhaust.

Push/pull on a rad usually gets @ 2-3°C better temps under heavy loads than push or pull alone, so I'm guessing you had other airflow issues than hot air from the rad, which got changed with the move from front/intake to top/exhaust. You'd have to be putting a huge amount (seriously, huge, like 200w+) into a 240mm AIO to get coolant temps beyond 40°C. I've run Prime95 small fft for over an hour and on my AIO, even with my OC being...
So my new rig contains:
I7 9700K
EVGA 2060 XC Ultra Gaming
MSI MPG Z390 (mobo)
3 Coolermaster Air Fans
1 360mm CPU cooler
Case is a Rosewill Prism S Lite. It has intakes on the bottom of the case and the PSU and Hard drive bay on top of the case.

What I was concerned about, which was brought up by others, is that the Radiator for the CPU cooler being used as an intake on the bottom of the fan will just cause hot air to be blown into the rest of the case. Now it is obvious that if the radiator was blowing out it would not be blowing "hot" air into the case. However my initial train of thought was that if I put the CPU cooler on the bottom of the case then it would be able to pull the coldest air into itself, therefore making it more efficient for the CPU.

Will this actually cause an issue with the rest of the computer where it will cause it to heat up, especially the GPU since it is blowing straight into it?

The tldr: you will be fine. With the exception of the gpu the rest of your system isnt as sensitive to heat.

However the gpu might run a few MHz lower. You can manually adjust the fan curve to be more aggressive. But the only true solution with a bottom mount radiator is to add a water block to the gpu and put that radiator as intake up front. Then exhaust top and rear.

Most people make the mistake of assuming the cpu should be water cooled first. Its typically middle to high end gpu cards that produce the most heat and need the most cooling.

You see a lot of aio kits for cpus because the sockets are standardized. No such luck with aib video cards. So hence why there are no kits commonly available.
 
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GodsArmada

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The tldr: you will be fine. With the exception of the gpu the rest of your system isnt as sensitive to heat.

However the gpu might run a few MHz lower. You can manually adjust the fan curve to be more aggressive. But the only true solution with a bottom mount radiator is to add a water block to the gpu and put that radiator as intake up front. Then exhaust top and rear.

Might want to look at the case for reference, but there is only a 240mm size spot for fans parallel to the mobo and the normal one in back. The PSU doubles as an an out since it is on the top of the case.
 
Might want to look at the case for reference, but there is only a 240mm size spot for fans parallel to the mobo and the normal one in back. The PSU doubles as an an out since it is on the top of the case.
Yes. I looked up the case for potential placement of your radiator and to see if a side fan was possible.

Thats why i suggested a 240 up front. I was suggesting using the psu as the top exhaust and a fan for the rear exhaust.
 
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GodsArmada

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Yes. I looked up the case for potential placement of your radiator and to see if a side fan was possible.

Thats why i suggested a 240 up front. I was suggesting using the psu as the top exhaust and a fan for the rear exhaust.
So there is a spot on the front of the case that I think I can screw two fans into, but its just a plate so idk how well it will vent. Do you mean the forward fan that is next to the mobo?
 

Karadjgne

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Ppl often confuse the cpu with the coolant temps. Coolant is in a constant battle with ambient air, not cpu temp. Tge cpu can be running 70°C and the coolant will be roughly 35°C. Case temps usually average 6°-12°C above exterior ambient temp, so in most air-conditioned areas, the outside will be @ 23°C, the air inside the case will be @ 29°C to 35°C. So at worst, you'd be putting 35°C air into a 29°C case, or adding 35°C air to 35°C air. No big deal, won't change anything when the gpu is blowing air across a 80°C heatsink.

The only reason it 'feels' hot is because to actually 'feel' that rad exhaust means removing the side panel, which drops case ambient to the same as the outside ambient, making the exhaust 'feel' hotter. With the case intact, it's pretty much all the same temp.
 
i used to have front intake aio for cpu, in idle all fine...cool air from rad.
during gaming, it was so hot (240mm rad with 4 intake fans), gpu got throttled (1070ti 375watt edition), while cpu was fine
moved rad to top as exhaust, gpu is doin fine now, while cpu tops at around 60 degrees now
 

Karadjgne

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I7 3770k @ 4.9GHz OC. Gtx970 OC 124%. Kraken x62 silent mode. Prime 95 small fft/msi kombuster. Mounted pull/intake Cpu 70°, gpu 82°. Mounted as push/top exhaust Cpu 72°, gpu 80°

4x 140mm fans total in Fractal Design R5 Window (not an impressive airflow case), front door closed. 2x intake, 2x top exhaust.

Push/pull on a rad usually gets @ 2-3°C better temps under heavy loads than push or pull alone, so I'm guessing you had other airflow issues than hot air from the rad, which got changed with the move from front/intake to top/exhaust. You'd have to be putting a huge amount (seriously, huge, like 200w+) into a 240mm AIO to get coolant temps beyond 40°C. I've run Prime95 small fft for over an hour and on my AIO, even with my OC being what it is, coolant has yet to go beyond 38°C, hdd stays around 35°C, gpu sitting right behind the rad idles at 33°C, with normal whole system idle being 32° on cpu, 33° on hdd, 32° on gpu.
 
Solution
So there is a spot on the front of the case that I think I can screw two fans into, but its just a plate so idk how well it will vent. Do you mean the forward fan that is next to the mobo?

I noticed the plate as well. But when I went straight to the product website, they do indeed have a graphic showing supported fan placement, and mounting holes for 120 and 240 fans. If there are indeed plates, I would guess they are punch out. Also the spacing from the front panel doesn't look ideal. So I'm guessing the flow from the front would be less than ideal itself.