[SOLVED] Can pointing another PC fan at PSU fan create voltage issues?

Aug 23, 2016
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I was wondering if pointing a PC case fan directly at my PSU fan (even on ECO mode) could possibly make it spin up or spin too fast causing a voltage spike that may damage my PC components.

I was going to put a Noctua A12x15 120mm FLX fan with the bottom of it approx 2" (its 15mm thick) below my EVGA G3 850 PSU fan, which is facing down surrounded by a metal shroud with a dust filter between them.

The Noctua fan runs at 1850 RPM, the PSU fan depends on system load, sometimes not spinning at all (ECO mode) and the Noctua fan starts as soon as my system is plugged in via USB power even before I turn it on.

Is this safe?

And since I'm generally trying to cool off the shroud itself from my vertical 3090 above it...should I have the airflow from the Noctua fan blow toward the PSU exhaust (I don't want them fighting each other) or away from it toward the shroud opening?

I'm having trouble without tearing my entire system down determining if its powerful enough to spin the PSU fan, and even then...would it increase the speed enough to be an issue or just blow cool air up to help it circulate...which is my goal.

The fan is entirely external, sitting about 2" below it while its off the ground give or take the 15mm thickness of it.

Is this even a remote concern?

Appreciate any input.
 
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So your saying its safe?

As much as I appreciate the history lesson and technical details (really, no sarcasm intended), since I prefer knowing how things worked from the start to understand everything now.

I was also able to swap my old Intel processor into the wrong type socket in a newer stock PC, start it up, watch it have a heart attack, swap it back and turn the PC back on. It still works to this day.....I doubt you could do that these days and get away with it lol.

So I just want to clarify if your answering my question and saying its ok to do it, or your just saying that was how it was designed back then as general information. It 'should' be safe is different from it 'is' safe, I believe it should be as well, but I...
Aug 23, 2016
57
9
4,545
pcpartpicker.com
In old computer system the CPU fan usually blows to the PSU's fan. Due to the common heatsink design, 50% goes to the PSU and 50% goes to the North Bridge's heatsink.

So your saying its safe?

As much as I appreciate the history lesson and technical details (really, no sarcasm intended), since I prefer knowing how things worked from the start to understand everything now.

I was also able to swap my old Intel processor into the wrong type socket in a newer stock PC, start it up, watch it have a heart attack, swap it back and turn the PC back on. It still works to this day.....I doubt you could do that these days and get away with it lol.

So I just want to clarify if your answering my question and saying its ok to do it, or your just saying that was how it was designed back then as general information. It 'should' be safe is different from it 'is' safe, I believe it should be as well, but I wasn't entirely positive.
 
So your saying its safe?

As much as I appreciate the history lesson and technical details (really, no sarcasm intended), since I prefer knowing how things worked from the start to understand everything now.

I was also able to swap my old Intel processor into the wrong type socket in a newer stock PC, start it up, watch it have a heart attack, swap it back and turn the PC back on. It still works to this day.....I doubt you could do that these days and get away with it lol.

So I just want to clarify if your answering my question and saying its ok to do it, or your just saying that was how it was designed back then as general information. It 'should' be safe is different from it 'is' safe, I believe it should be as well, but I wasn't entirely positive.

Of course it's safe, moreover even when the PSU fan isn't spinning, the PSU would still receive some airflow.
 
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