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MADRGB
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First time building a water loop. Using hydro X components for it.

Im a noob concerning this but not to when it comes to building air cooled PC´s.

So, and forgive the noobness, what the heck do I plug into the cpu fan header to avoid bios warning on boots? Radiator fans?

According to Corsairs instruction the 4 pin pwm on the pump has to go into the Cpro. So I assume thats not an option.

 

Secondary question. Im running gpu and cpu block. Im not sure whether to go for 2 x 360mm slim radiators or a beefy 480mm 54mm radiator. Would I even notice any difference? Im leaning to the latter for a cleaner build.

Edited by MADRGB
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one 54mm rad doesn't equal two 25mm ones :)

There's diminishing return to using very thick rads since the air is gradually heated as it travels through the radiator. The exhaust side of the fins will be warmer than the intake side. Of course one would have to test it to get numbers but i believe running two 360mm will get you way better thermals.

 

Regarding the CPU fan alarms, you can disable it in BIOS. Since the motherboard doesn't manage fans, it's not needed at all. You'll still get temperature warning beeps if anything goes wrong.

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Specifically for Asus, the CPU fan warning system is quietly tucked away in the Advanced BIOS -> Monitor column. Scroll down about 15 lines until you see the CPU Fan header speed. Hit enter and it will present an "ignore" option. The boot warning is now disabled. the only reason to have this engaged is if your cooling functionality is actually tied to a signal or device on that header. You will have plenty of other ways to detect this and with water its not the same as someone who booted up without an air cooler in place.

 

In most circumstances a 480mm radiator loses out to 2x360mm. As mentioned, thickness is not quite as valuable as fan surface area, so 4x120 vs 6x120. In order to take advantage of thicker radiators, you must run higher fan speeds. It depends on density, but most are not better than their skinnier counterparts until at least 1500-1800 rpm. Many are looking to avoid that state instead of embracing it. So you can let your 2x360x30mm float along at 1000 rpm and the 480x54 probably needs 1600-1800 rpm to stay even.

 

The only situation were I might be more inclined to go with the 480mm would be in terms of airflow management. If the case (for whatever reason) is going to force you to dump air from radiator into the other, then you really aren't working with two fully functional radiators. In that circumstance, the single 480mm would be better since the other pair is really 1 working 360mm and the other warms the coolant back up as it passes through.

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Specifically for Asus, the CPU fan warning system is quietly tucked away in the Advanced BIOS -> Monitor column. Scroll down about 15 lines until you see the CPU Fan header speed. Hit enter and it will present an "ignore" option. The boot warning is now disabled. the only reason to have this engaged is if your cooling functionality is actually tied to a signal or device on that header. You will have plenty of other ways to detect this and with water its not the same as someone who booted up without an air cooler in place.

 

In most circumstances a 480mm radiator loses out to 2x360mm. As mentioned, thickness is not quite as valuable as fan surface area, so 4x120 vs 6x120. In order to take advantage of thicker radiators, you must run higher fan speeds. It depends on density, but most are not better than their skinnier counterparts until at least 1500-1800 rpm. Many are looking to avoid that state instead of embracing it. So you can let your 2x360x30mm float along at 1000 rpm and the 480x54 probably needs 1600-1800 rpm to stay even.

 

The only situation were I might be more inclined to go with the 480mm would be in terms of airflow management. If the case (for whatever reason) is going to force you to dump air from radiator into the other, then you really aren't working with two fully functional radiators. In that circumstance, the single 480mm would be better since the other pair is really 1 working 360mm and the other warms the coolant back up as it passes through.

 

Thank you for that detailed explanation. My reason for leaning for a 480mm is also aesthetics to be honest. Case is Core P8. Where ever I would place 360mm rads there would be an empty "slot" if you can follow me. Which is why I am considering the Corsair X7 480mm radx1 instead of 2 x 360mm XR5.

Edited by MADRGB
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And I think that case qualifies in the special exception category. If you are going to use it in semi-open mode, the single 480mm is going to do very well with a really low intake side air temp and you're blowing heat out the back. Definitely a certain elegance and simplicity to that. If you are going to close it up, then I am not sure how those radiators work with a piece of glass resting against one side or the other. Let's theorize not all that well.

 

In the open set-up, 1x480 is going to be fine. If are going to go closed, it takes the open air advantage out. The other option would be to do some combination of 480+360 with the other 360mm up top. I would think taking the top and small side glass off would be the easiest and least visually offensive while offering measurable performance advantages.

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And I think that case qualifies in the special exception category. If you are going to use it in semi-open mode, the single 480mm is going to do very well with a really low intake side air temp and you're blowing heat out the back. Definitely a certain elegance and simplicity to that. If you are going to close it up, then I am not sure how those radiators work with a piece of glass resting against one side or the other. Let's theorize not all that well.

 

In the open set-up, 1x480 is going to be fine. If are going to go closed, it takes the open air advantage out. The other option would be to do some combination of 480+360 with the other 360mm up top. I would think taking the top and small side glass off would be the easiest and least visually offensive while offering measurable performance advantages.

 

First of all thank you again for the rpoly, really helpful.

Dont you mean top and front glass? Im considering sidemounting that 480mm and having it exhausting on the rear side. Then either:

 

A: leave all glass panels on with intake front and bottom and exhaust back and top

B: Leave the front open, no fans, but the rest the same as above. Thoughts?

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I can't add much more to that without ever having worked with the case or one of the smaller variants. As to the glass, I was thinking more in terms of visual aesthetics with the large parallel piece on the and the rest of the case open. How that practically works in terms of mounting I don't know. Might be one of those times where you need the case in hand to really make a decision.
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  • 1 month later...

Just wanted to update now the build is finished and have been running for 2 weeks. Thought maybe the 2 x 360 vs 1 x 480 54mm radiator discussion and cooling result using the latter could be of general interest regarding temps.

 

In ambient 20-21 celcius I get, idle/load (Realbench/Firestrike):

 

CPU (10850K 5ghz all cores): 31/78

GPU (Rog Strix 3080 OC +50mhz OC on top of factory OC): 23/43

 

Pump running fixed at 65%. Fans running fixed at 75%.

 

This is with a closed build, all glass panels on.

 

https://www.flickr.com/photos/192404664@N06/shares/4s5PZW

Edited by MADRGB
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