A4000T PSU slowly ramping up in fan speed under normal load

8bitbubsy · 03 March 2017, 11:54

My A4000T PSU is the original that came with it (250W), but for some reason the fan speed is slowly ramping up under a course of 10-15 minutes, going from comfortably quiet to semi-annoying. I'm drawing ~45w out of it using a watt-meter and one would think that the fan speed should've staid at a constant speed then. I have also recapped the PSU with genuine Nichicon low-ESR, so there shouldn't be any leaky or high-ESR caps in there.

Is this normal for an A4000T PSU under idle loads? If not, then I'd suspect a resistor or transistor, but it's a good idea to ask if this is normal first.

03 March 2017, 11:54	#1
8bitbubsy Registered User Join Date: Sep 2009 Location: Norway Posts: 1,710	A4000T PSU slowly ramping up in fan speed under normal load My A4000T PSU is the original that came with it (250W), but for some reason the fan speed is slowly ramping up under a course of 10-15 minutes, going from comfortably quiet to semi-annoying. I'm drawing ~45w out of it using a watt-meter and one would think that the fan speed should've staid at a constant speed then. I have also recapped the PSU with genuine Nichicon low-ESR, so there shouldn't be any leaky or high-ESR caps in there. Is this normal for an A4000T PSU under idle loads? If not, then I'd suspect a resistor or transistor, but it's a good idea to ask if this is normal first.

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