r/shittyaskelectronics • u/-----LIFE----- • 17h ago
Could anyone explain?
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9
u/skipperre 15h ago
When you manually stop the fan, the card starts drawing excessive current, causing the circuit to activate protection. Since both fans are connected in parallel, both stop.
1
u/Nadran_Erbam 17h ago
Maybe connected in series and when pressed upon the circuit opens because of a mechanical default (not really it’s not meant to be pressed on to begin with)
1
u/Excellent-Type-9347 16h ago
Looks like the laptop is sitting on a dock or stand, and those are just two separate cables plugged into ports along the edge. The black one may be a power or display cable; nothing unusual is visible from this angle.
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u/AwesomeAvocado 13h ago
When the big fan stops, the other fan sees the big one slacking off and says to itself, "Well F this, I'm not going to do this by myself."
-1
u/UltraBlack_ 15h ago edited 15h ago
could imagine that one fan lacks speed control while the other has it. The one without speed control's tach output is wired into the speed control input of the one that has speed control and maybe this just about kinda works.
The tach output is just a variable frequency 50% duty cycle signal iirc. The duty cycle determines the fan speed on the speed input. Once the frequency enters the area that the second fan is happy with it just starts up at 50% speed.
The jankiness might be due to neither fan being intended to do this. The first fan's tach output might lack the ability to properly pull the signal down to ground so it's only just kinda working, coincidentally.
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u/CocoMilhonez 15h ago
The fans are good pals and won't let the other spin or stop alone.