[SOLVED] Case fan slowing down while playing a game

iam480p

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Oct 18, 2017
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Hello. My case fans slows down when a heavy scene from a game is playing, leading to a crash sometimes. When the worst happens, the PC itself shuts down. I thought it was because of a power supply issue. But, I could be wrong. I need your opinions as to why this happens. My case fans are daisy chained since my motherboard only supports one fan header.

PC Specs below:
AMD Ryzen 5 2600
Gigabyte A320M-S2H rev 1.1
HyperX 16gb DDR4
XFX RX 480 GTR 8GB
InWin Jupiter AJ120
Cougar SL500
 
Solution
First check if your fan curve is set correctly, it may have set to slow down when it hits a higher temperature. You can do this in the BIOS. If its correctly set up, your fans may not be getting enough power from a single PWM fan header since it can only power so much. Try connecting only 1 fan and see if it ramps up, if it does, its likely that the PWM header cannot handle more fans.

LazerTechX

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May 3, 2014
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First check if your fan curve is set correctly, it may have set to slow down when it hits a higher temperature. You can do this in the BIOS. If its correctly set up, your fans may not be getting enough power from a single PWM fan header since it can only power so much. Try connecting only 1 fan and see if it ramps up, if it does, its likely that the PWM header cannot handle more fans.
 
Solution

Paperdoc

Polypheme
Ambassador
LazerTechX is correct to point to a possible power limit. For more complete info, tell us:
  1. What maker and exact model of mobo?
  2. Case fans - maker, model nunber, and how many?

With that we can look up power requirements vs. mobo ability and advise.
 

iam480p

Honorable
Oct 18, 2017
43
1
10,535
LazerTechX is correct to point to a possible power limit. For more complete info, tell us:
  1. What maker and exact model of mobo?
  2. Case fans - maker, model nunber, and how many?
With that we can look up power requirements vs. mobo ability and advise.

My motherboard is the Gigabyte A320M-S2h rev 1.1
My case fans are 3 Inwin Jupiter AJ120 and 1 corsair 120mm fan with a 3 pin.

My case fans are 4-pin PWM and the corsair one is 3-pin.
 

Paperdoc

Polypheme
Ambassador
Unfortunately I could not get a manual for that mobo to download, so I can only say that almost all mobo fan headers can supply up to 1.0 A current to all fans connected. Your three Inwin fans' motors pull 0.20 A max each. The corsair 3-pin likely pulls no more than that, maybe a bit less. So all four in a daisy chain from one header would be quite acceptable. They should NOT overload the header unless the Corsair is an odd fan, like an older LED Fan with lights but NO separate lighting cable.

It is important that you configure the fan header properly. It must be set to use the newer PWM Mode of control, not DC or Voltage, and not Auto. Also, IF there is an option for this, the header for these case fans should be set to use the temperature sensor on the mobo, and not the one inside the CPU chip.

However, there is a speed control issue. You can NOT conrol the speed of a 3-pin fan with the PWM system. So with your combination, the three 4-pin fans' speeds should be controlled by the PWM system, but the 3-pin Corsair you stuck on the end of the daisy chain should always be running full speed. If you want that Corsair's speed controlled and IF you have an unused SYS_FAN header, connect it there by itself and configure that header to use Voltage Control Mode (aka DC Mode).
 

iam480p

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Oct 18, 2017
43
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Unfortunately, I don't have an extra SYS_FAN header because the board that I got is an entry level one. Should I upgrade the power supply then? Is that a more viable option?