Can Rear case fan interfere with CPU fan?
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Can Rear case fan interfere with CPU fan?
Did a quick search but anyway,
If my audible rear case fan is under-volted, producing less CFM than the the CPU fan. 1) Does the rear case fan hinder CPU fan flow. 2) Would the CPU fan alone provide better exhaust out the back (over the VRM's). Is it better to remove the (only) case fan?
Note: The CPU and rear case fan are about 2" apart, in-line and blow rear. I like to think of the simplified version of two fans mounted at both ends of a tube (one with lower CFM).
If my audible rear case fan is under-volted, producing less CFM than the the CPU fan. 1) Does the rear case fan hinder CPU fan flow. 2) Would the CPU fan alone provide better exhaust out the back (over the VRM's). Is it better to remove the (only) case fan?
Note: The CPU and rear case fan are about 2" apart, in-line and blow rear. I like to think of the simplified version of two fans mounted at both ends of a tube (one with lower CFM).
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Re: Can Rear case fan interfere with CPU fan?
It depends. There are many variables, like relative fan speeds, and whether there are other vents in the case nearby. I doubt the two fans give you much of a cooling advantage. It should like the CPU fan is mounted sucking air through the fins towards the back? You'd get more advantage mounting it on the other side blowing into the fins instead so you get a real push/pull effect with the 2 fans. Which cooler, CPU, case, fans etc?
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Re: Can Rear case fan interfere with CPU fan?
Thanks for he reply. The CPU fan pulls air through the cooler. The ram interferes with the fan when it's mounted on the other side.MikeC wrote:the CPU fan is mounted sucking air through the fins towards the back?
Is it true airflow is also better on the fan's exhaust side (I remember something like that)? Anyway these sound like good reasons to find a way to do that.MikeC wrote:You'd get more advantage mounting it on the other side
Going for a quiet PC sound system this time around: Core I5 2500k w/ full tower Gelid Tranquillo CPU cooler. A 120mm Nexus @12v is mounted to the cooler and another @7v is at the rear of the case. FIY I recently took out the front 140mm fan and HDD cages from the Lian-Li PC-6 case. There was little difference to the observable temps (don't know about the VRM's). Ordered an Accellero S1 GPU cooler with another Nexus 120mm for the Radeon 7870 (my Nvidia 570 died). So 3 active fans altogether not including the Seasonic 560 PSU fan which stays quiet.MikeC wrote:Which cooler, CPU, case, fans etc?
Re: Can Rear case fan interfere with CPU fan?
CPU fan does not fit because of RAM modules with a big nonsense heat spreader i guess?
Sell the RAM and get low ones which do not interfere and solve your Problem by mounting the CPU fan as it is meant to be.
Setting the CPU fan @12v seems to high, but with the data supplied i cannot say any more.
Sell the RAM and get low ones which do not interfere and solve your Problem by mounting the CPU fan as it is meant to be.
Setting the CPU fan @12v seems to high, but with the data supplied i cannot say any more.
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Re: Can Rear case fan interfere with CPU fan?
iirc, the Tranquillo samples we encountered had convex bases, not great for heat transfer. You could try lapping the HS, using a fairly coarse grade of sandpaper -- say 300? -- and finishing with perhaps 6-800. Also just remove the heatspreaders on the RAM. Most often useless. Done carefully, this is easy -- I've done it many times, as the RAM that goes on sale most often seems to be the ridiculously headspread type.
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Re: Can Rear case fan interfere with CPU fan?
Thanks, the ram is standard Corsair. Actually i'm not worried about CPU temps right now as the cooler seems effective (45c max w/ prime 95). I would really, really like to take out the rear case fan though; especially if it contributes nothing (or hinders? cooling). Just a bit worried about the VRM's.
edit: I do have a temperature probe. Would simple contact with the VRM's provide a good thermal estimate?
edit: I do have a temperature probe. Would simple contact with the VRM's provide a good thermal estimate?
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Re: Can Rear case fan interfere with CPU fan?
On second thought I'll find a way to go with the standard push-pull setup mentioned, and bypass these questions. Much easier and if the fans can run @ 7v I should be happy.
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Re: Can Rear case fan interfere with CPU fan?
Good plan. Let us know how it works out.picture_perfect wrote:On second thought I'll find a way to go with the standard push-pull setup mentioned, and bypass these questions. Much easier and if the fans can run @ 7v I should be happy.
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Re: Can Rear case fan interfere with CPU fan?
Thanks, this site has been invaluable over the years.